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Name: ________________________________ Period: _____ Unit 3: Periodic Table Unit Notes & CW Unit Objectives: Describe the origin of the periodic table State the modern periodic law Explain how an element’s electron configuration is related to the element’s placement within a period and a group on the periodic table. State the trends of the following properties within periods and groups of elements including: o Ionization energy o Electronegativity o Atomic Radius o Reactivity o Metallic/Nonmetallic character Identify and state the properties of the following groups in the periodic table: o Alkali metals o Alkaline earth metals o Halogens o Noble Gases o Transition elements Locate within the periodic table and state the properties of the metals, nonmetals, and metalloids (semi-metals) Define the following vocabulary: Allotrope Nonmetals Ion Metalloids Cation Luster Anion Malleability Electron Ductility Proton Conductivity Neutron Nonmetals Compound Brittleness Element Dull Valence electron Non-conductor Lewis Dot Diagram Noble gas Metals Periodic Law Mendeleev Period Group(family) Alkali Metals Alkaline Earth Metals Halogens Atomic radius Ionization energy Electronegativity Reactivity Electron configuration Stable Octet 1 The bold, underlined words are important vocabulary words that you should be able to define and use properly in explanations. This is a study guide for what you will be tested on throughout the year. The objectives are divided into categories of “Knowledge” (what you have to know) and “Application” (what you have to be able to do). THE PERIODIC TABLE o 1. o o o 2. o 3. 4. o o 5. 6. 7. o o o Knowledge The placement or location of an element on the Periodic Table gives an indication of physical and chemical properties of that element. The elements on the Periodic Table are arranged in order of increasing atomic number. The number of protons in an atom (atomic number) identifies the element. This goes at the bottom left corner of the symbol for that element. The sum of the protons and neutrons in an atom (mass number) identifies an isotope. The mass number is placed at the top left corner of the symbol for an element OR is placed after the element symbol or name and a dash. Ex: Three different ways to write carbon with a mass number of 14: C, carbon-14, or C-14 Application o Explain the placement of an unknown element in the periodic table based on its properties o Interpret and write isotopic notations. Ex: C-12, C-13, and C-14 are isotopes of the element carbon o Identify the properties of metals, metalloids, nonmetals and noble Elements are classified by their properties, and located on the gases periodic table as metals, metalloids, nonmetals, or noble o Classify elements as metals, gases. metalloids, nonmetals, or noble gases by their properties o An element’s atomic radius, first ionization energy, and electronegativity determine its physical and chemical properties Substances can be differentiated by their physical o Identify and give examples of properties. physical properties Physical properties of substances include melting point, boiling o Describe the states of the point, density, conductivity, malleability, solubility, and elements at STP (solid, liquid, or hardness. gas). (Table S) o Identify and give examples of chemical properties Substances can be differentiated by chemical properties. o Describe the difference between Chemical properties describe how an element behaves during a physical and chemical properties of chemical reaction and include reactivity, flammability, and substances toxicity. o Some elements exist as two or more forms in the same phase. These forms differ in their molecular or crystal structure and therefore in their properties. The word to describe this phenomenon is ALLOTROPE. o Ozone and oxygen gases are allotropes of each other. Ozone is O 3 and it is very dangerous to our health. Oxygen gas is O2 and we need it to survive. 2 o Diamonds and graphite (better known as pencil lead) are both forms of the element carbon. They have different molecular structures and very different properties. o Determine the group of an o For Groups (also called families) 1, 2, and 13-18 on the Periodic element, given the chemical Table, elements within the same group have the same number of formula of a compound valence electrons (helium is the exception) and therefore similar Ex: A compound has the formula 8. chemical properties. XCl2, element X is in Group 2 o Elements in the same Period (row) have the same number of o Determine the number of energy principal energy levels (shells) which contain electrons. levels containing electrons given an element’s Period and vice versa o The succession of elements within the same GROUP (top to o Compare and contrast properties bottom) demonstrates characteristic trends: differences in of elements within a group or a 9. atomic radius, ionic radius, electronegativity, first ionization period for groups 1, 2, and 13-18 energy, and metallic/nonmetallic properties. on the periodic table o The succession of elements across the same PERIOD (left to o Understand and be able to explain right) demonstrates characteristic trends: differences in atomic 10. the trends in terms of nuclear radius, ionic radius, electronegativity, first ionization charge and electron shielding energy, and metallic/nonmetallic properties. Goal setting: Based upon your learning style results and the information above list at least two techniques you plan to use to study during this unit. 1. 2. What grade would you like to achieve on this unit based on your efforts? _______% 3 Activity - Writing Your Name using Chemical Element Symbols Objective In this activity, you will use your creativity to spell your name (first or middle name and your last name) using chemical symbols of elements on the periodic table. For example, you can spell Yvonne using the symbols for yttrium (Y), vanadium (V), oxygen (O), nitrogen (N), and neon (Ne). Materials Ruler Pencil Colored pencils Markers Poster board 8.5 x 11 sheets of copier paper IUPAC Periodic Table of the Elements Computer or Chrome book Procedure Your poster must include: The chemical element symbols used to spell your name (first or middle name and last name). o If your name has the letter J, use J and the information for Iodine (J was the former symbol for Iodine). o If you are only using the first letter of a two-lettered symbol, still include the second letter, but fade the letter so it does not appear that it is used in the spelling (see example at the end of the activity). Box drawings of the symbols as they appear in the IUPAC periodic table of the elements (including atomic number, atomic mass, symbol, and element’s name). The following information for at least four of the elements you use (typed and printed on the copier paper and attached to the bottom of the poster board): o Physical description of the element: metal, nonmetal, or metalloid; solid, liquid, or gas at room temperature, or synthetic. o Group number and period number where the element is located in the periodic table. o Description of the atomic structure of the atoms of the elements: Number of protons and neutrons in the nucleus, and the number of electrons found in the electron cloud. o At least two chemical and physical properties of the element. o The description of at least two common uses of the element. o When was the element discovered and who discovered it. Each element’s box should be at least 5.4 cm wide and 6 cm tall on the poster. The poster should be organized neatly and created in color. Presentation of your poster to the class: The presentation should include saying what elements did you use to spell your name and last name, the element’s properties and the description of at least two common uses of the element for the four elements you picked. 4 Useful websites: http://www.lenntech.com/periodic/periodic-chart.htm http://www.webelements.com http://chemicalelements.com/ http://www.rsc.org/periodic-table/ http://www.iupac.org/fileadmin/user_upload/news/IUPAC_Periodic_Table8Jan16.pdf Example For example, if your name is Yvonne Wilson, you could write it using the elements Y, V, O, N, Ne, W, I, Li (notice that the i from the Li symbol is shaded grey since it is not part of the spelling), S, O, and N. Notice that the sizes and shapes of the boxes are different from the instructions given above, in order to fit the space available below 39 Y ytrium 88.91 74 W tungsten 183.8 23 V vanadium 50.94 53 I iodine 126.9 7 N nitrogen 14.01 8 O oxygen 15.99 3 Li lithium 6.938 16 S sulfur 32.05 10 Ne neon 20.18 8 O oxygen 15.99 7 N nitrogen 14.01 Rubric Element Name (1 point) Atomic Number (1 point) Atomic Symbol (1 point) Atomic Mass (1 point) Number of protons, number of neutrons, and number of electrons (3 points) Physical descriptions: metal, non-metal, metalloid, density, physical state at room temperature (2 points) Uses (at least 2 common uses) (2 points) Group, period (2 points) At least two chemical or physical properties of the element (2 points) Neatness, spelling, color, creativity (3 points) List of sources of information (books, websites, magazines, etc. (can be pasted to the back of poster (4 points) Year discovered and discoverer (4 points) Your name and date (on back of poster) (4 points) Poster presentation to the class (20 points) 5 Lesson 1: The History of the Table &Chemical Periodicity Objective: To relate the work of chemists to the modern periodic law and the repeating patterns in the periodic table Watch the following clip: History & structure of the periodic table Dmitri Mendeleev (Russia) Between 1868 and 1870, in the process of writing his book, The Principles of Chemistry, Mendeleev created a table or chart that listed the known elements according to increasing order of atomic weights. When he organized the table into horizontal rows, a pattern became apparent--but only if he left blanks in the table. If he did so, elements with similar chemical properties appeared at regular intervals--periodically--in vertical columns on the table. Mendeleev was bold enough to suggest that new elements not yet discovered would be found to fill the blank places. He even went so far as to predict the properties of the missing elements. Although many scientists greeted Mendeleev's first table with skepticism, its predictive value soon became clear. The discovery of gallium in 1875, of scandium in 1879, and of germanium in 1886 supported the idea underlying Mendeleev's table. Each of the new elements displayed properties that accorded with those Mendeleev had predicted based on his realization that elements in the same column have similar chemical properties. The three new elements were respectively discovered by French, a Scandinavian, and a German scientist, each of whom named the element in honor of his country or region. (Gallia is Latin for France.) Discovery of a new element had become a matter of national pride--the rare kind of science that people could read about in newspapers, and that even politicians would mention. Periodic = cyclic; repeating patterns/cycles; similar to monthly/weekly calendar (days of the week) Ex: tired on Mondays, happy on Fridays Henry Moseley (England) By 1907, when Mendeleev died, chemists were sure that iodine followed tellurium in the Periodic Table and that there was something odd about their relative atomic masses. However no-one was able to measure atomic number, it was just the position of an element in the Periodic Table sequence. For example lithium was known to be the third element but this number three was only because its properties meant that it slotted in between helium and beryllium. Henry Moseley found and measured a property linked to Periodic Table position. Hence atomic number became more meaningful and the three pairs of elements that seemed to be in the wrong order could be explained. Moseley used what was then brand-new technology in his experiments. A device now called an electron gun had just been developed. He used this to fire a stream of electrons (like machine gun bullets) at samples of different elements. He found that the elements gave off X-rays. (This is how the X-rays used in hospitals are produced.) Moseley measured the frequency of the X-rays given off by different elements. Each element gave a different frequency and he found that this frequency was mathematically related to the position of the element in the Periodic Table – he could actually measure atomic number! Periodic Law = 6 How is the table actually arranged? Periods = The period number The properties of elements change drastically across a period from . The number of valence electrons increases from left to right (1 à 8) 2. Groups (Families) = Example: K in Group 1 Let’s look at the electron configuration of elements in the same group… H=1 Li = 2-1 Na = 2-8-1 K = 2-8-8-1 Rb = 2-8-18-8-1 Cs = 2-8-18-18-8-1 *Fr = -18-32-18-8-1 What similarities can you observe within the above electron configurations? Remember… Group # = Period number = Why do elements in the same group have similar chemical/physical properties? Reactive elements can bond easily with other elements. They have an incomplete valence electron shell. All atoms (except hydrogen and Helium) want 7 Most elements, except noble gases, combine to form compounds. Compounds are the result of the formation of chemical bonds between two or more different elements. In the formation of a chemical bond, atoms lose, gain or share valence electrons to complete their outer shell and attain a noble gas configuration. This tendency An ion (charged particle) can be Isoelectronic: atoms or ions that have the SAME number of ELECTRONS Ex: F-, Ne, and Na+ all have 10 electrons Octet = ****KNOW THIS!!!!**** 8 Activity - Make a Periodic Table Background The periodic table is special way of arranging elements based on their properties and characteristics. Purpose To create a periodic table using imaginary elements. This periodic table should have appropriate trends across rows and groups of elements. Materials • • One set of element cards One blank periodic table template Procedure 1. On the next page, you will see a collection of elements along with their characteristics. 2. Cut each element card and arrange the elements in order based upon their characteristics, just like you would see on the periodic table. Use the attached periodic table template. (Note: Not all spaces on the template will be filled – there is a missing element!) 3. When you have finished, have your teacher check your work. 9 solid gas Pa Az 71.7 red 102.2 light blue gas solid Tx 92.4 pink liquid brittle solid Ia Ma Fl ? blue 55.9 hunter green 99.6 yellow solid gas solid Ak Tn Nj 104.3 light green 67.8 dark blue 81.2 green brittle solid Cn 37.2 orange solid Ut 16.3 crimson 10 11 Classwork 3-1: 12 Model: An Electron Dot Diagram of the Elements Task: Below the symbol for each element, write an electron configuration for the elements in the model. Lithium has been done for you. Questions: 1.) How are the members of the same column (group) similar in terms of the number of valence electrons? 2.) Which group contains the least number of valence electrons? 3.) Which group contains the largest number of valence electrons? 4.) Which row (period) contains three occupied shells? 5.) How are the members of the same period similar in terms of the number of energy levels (shells)? 6.) Are atoms with a larger radius more likely to be found at the top or bottom of a group (column)? Explain your answer. 7.) In terms of the number of valence electrons, describe one cyclic property that can be observed in the model. 8.) Which group would be considered non-reactive? Why? 9.)When atoms form ions, the electron configuration of the ion resembles the electron configuration of a CERTAIN noble gas. Which Noble Gas will each of these atom’s ions be like? a. Sr c. Br e. Al g. Li______ b. O d. Si f. P h. Cs ____ 13 Practice: It’s Elemental DIRECTIONS: Use the reading below to answer the questions that follow. We all know by now that the periodic table is arranged according to increasing atomic number. What we’re only beginning to learn is the significance of elements within the same column (vertical) and row (horizontal) on the table. Every element found within a given row, or period, has the same number of electron shells, or principle energy levels. Despite this one common feature, atoms of one element within a given period do not behave similar to atoms of another element in that same period. In fact, the period in which an element is found really tells you nothing about how the atoms of that element will behave. The only additional thing that we can really say about elements of the same period is that they increase by very little in terms of size (or mass) as we go from left to right on the table since the atomic number( number of protons) only goes up by one. Look at the periodic tables that you labeled and colorcoordinated. Look at how much the mass increases as you move from left to right in a given period. Every element found within a given column, or group, has the same number of valence electrons. This is VERY significant because it’s the number of valence electrons that determines how atoms of any element are going to “behave.” When we say “behave,” what we really mean is how they’re going to react, or bond with atoms of other elements. However, not all columns or groups qualify as “families.” In fact, the only groups that are considered to be families are Group I (Alkalai Metals), Group II (Alkaline Earth Metals), Group XVII (Halogens), and Group XVIII (Noble Gases). The behaviors of the transition metals are very difficult to predict, and the behavior of the elements within the BCNO group varies greatly from one element to another. An element’s family tells you much more about its properties than its period does. All of the elements in the Halogen family have 7 valence electrons. There’s an easy way to cheat when it comes to determining the number of valence electrons. Just look at the last digit of the group number above the first element in the family. For the first two families (alkali metals and alkaline earth metals) it’s a single digit number, so there’s no confusion. Alkali metals are group 1, which means all elements in that family have 1 valence electron. The halogen family, on the other hand, is group 17, which means they have how many electrons in their valence shell? If you said 7, you’re right. This trick will help you when it comes to drawing Lewis dot diagrams… Speaking of the Lewis dot diagram, it’s used to show only the valence electrons in a given atom or compound. After all, the valence electrons are the only electrons involved in bonding. There are four basic spots that an electron can occupy in a Lewis dot diagram because the maximum number of valence electrons that an atom of an element can generally hold is eight. If the element symbol was the face of a clock, the spots would be at 12 o’clock, 3 o’clock, 6 o’clock, and 9 o’clock. The first spot is like a taxi cab that can hold two electrons in its single seat. The remaining three spots are like seats on a bus that can also hold electrons. Just as you would do if you got onto a bus, electrons look for empty seats first. Once the taxi cab is full, the remaining electrons in the valence shell occupy empty “seats.” Only after each of the three seats has an electron in it do they begin to pair up. The exceptions to the octet rule are elements that have only one energy level or seek to have one energy level. These elements include hydrogen, helium, lithium, beryllium, and boron. These elements also seek to have a full valence shell, but it will only contain two electrons. Otherwise, there can never be more than 8 valence electrons and, no matter what, there can never be more than 2 electrons in a given “seat.” All atoms seek to have a full valence shell, and the easiest way to do that is to form bonds with other atoms. We mentioned before that atoms in the family of noble gases already have a full valence shell, and that’s why they rarely ever seek to bond with other atoms. For all other element families, the atoms seek to form bonds in order to complete their valence shell. As a general rule, the number of unpaired valence electrons tells you the number of bonds that atoms of a given element “like” to form. Halogens, like chlorine (Cl), have 7 valence electrons and only one unpaired valence electrons. That means that the halogens have two choices: They can either steal an electron, usually from an atom with only 1 valence electron, like sodium (Na), forming what we call an ionic bond. The other choice an atom like chlorine has is to share an electron with an atom that’s also one short of having a full valence shell, like another chlorine atom. This sharing of electrons is an example of a covalent bond. As we said before, carbon has 4 valence electrons, which means that all of them can occupy a seat unpaired for a maximum of 4 unpaired valence electrons. That’s why 14 carbon looks to share each of its 4 single valence electrons in order to end up with 4 pairs instead, giving it the full 8 it needs to fill its valence shell. In other words, carbon will form 4 covalent bonds. A single line is used to illustrate a bond between two atoms, and each single line represents 2 electrons. 1. How is the periodic table arranged? 2. What do we call the horizontal rows of the periodic table? What do all the elements in a given row have in common? 3. What do we call the vertical columns of the periodic table? What do all the elements in a given column have in common? 4. Which tells us more about an element’s properties, its row or its column? Why is this? 5. Which of the following elements is chlorine (Cl) most similar to? a. b. c. d. fluorine (F) sulfur (S) oxygen (O) argon (Ar) 6. Does mass increase more as we go from left to right or top to bottom on the periodic table? 7. Are atoms of the elements in the family of noble gases reactive (do they readily form bonds with other atoms)? Why is this? 8. How are ionic bonds formed? 15 9. How are covalent bonds formed? 10. What determines how many bonds an atom will form? 11. What is the easiest way for atoms without a full valence shell to gain a full valence shell? 12. If an atom of an element has four valence electrons, what is the maximum number of unpaired electrons it can have? Draw a Lewis Dot diagram of an element that fits this description. 13. Draw a Lewis Dot diagram of an element with 6 valence electrons. How many bonds can it form? 14. Why do chlorine (Cl) and sodium (Na) bond so easily with one another? 15. Which element, carbon (C) or fluorine (F) would you expect to be more reactive? Explain your answer. (Hint: Think about which element is closer to its goal.) 16 Lesson 2: Key to the Periodic Table Objective: To define the location and compare and contrast the properties of metals, nonmetals, and metalloids. Check this out! Interactive Periodic Table The structure of the periodic table gives us a lot of information. Depending on an element’s position in the table, we can determin a lot of its physical and chemical properties. Metalloids 1. Metals: due to 2. Nonmetals: 17 3. Metalloids (AKA semi-metals): The Groups in more detail Group 1 à Group 2 à 18 Groups 3-12 à Found in the MIDDLE of the table (the D block) Tend to be UNPREDICTABLE will lose electrons or gain them depending on what other METALS are present Groups 13-16 BCNO groups (not a single group) MISCELLANEOUS groups Metals, nonmetals, & metalloids found along the staircase (many different properties) Group 17 à Form SALTS/COMPOUNDS called HALIDES All NONMETALS making up the group Group 18 à Most STABLE group; exist ALONE in nature. Non reactive! Ex: Neon (Ne) Hydrogen Not officially part of a group Can be seen as H2(g), H+(aq) or H-(aq) The Lanthanide/Actinide Series Two rows on bottom of table (detached) – Elements 58 – 71 & 90 - 103 Actually belong to the TRANSITION METALS 19 Activity - Organization of the Periodic Table Directions Using your computer, tablet or mobile device, navigate to the website: www.ptable.com You will interact with this periodic table to find the answers to the questions below. *Make sure the “Wikipedia” tab is selected in order to answer the following questions: 1. The vertical columns on the periodic table are called groups, how many groups are there on the periodic table? 2. The horizontal rows on the periodic table are called periods, how many periods are there on the periodic table? 3. Using the group and period numbers, identify the elements that are located in each of the following location. a. The element in group 10 and period 5 = b. The element in group 15 and period 4 = c. The element in group 2 and period 3 = d. The element in group 18 and period 6= e. The element in group 1 and period 7 = 4. Are most of the elements on the periodic table classified as a metal or a non-metal? 5. Are the non-metal elements located on the left or right side of the periodic table? *Elements can also be classified by family, use the color coding at the top of the page to help identify the family names and their element members. 6. How many elements belong to the Alkali Metal family? List the member elements by their symbol. 7. Click on the group number for the Alkali Metals family at the top of the table. Answer the following about the Alkali metals: a. What are 3 similar properties of these elements? b. Where are these found naturally? c. What is a common substance that alkali metals react vigorously with? 20 8. What type of element does the neon green color indicate? List the element symbols for the elements that are designated with neon green below. 9. How many elements belong to the Halogen family? List the member elements by their symbol. 10. Click on the group number for the Halogen family at the top of the table. Answer the following about the Halogen elements: a. What does the name “halogen” mean? b. What type of molecule is formed when a halogen combines with hydrogen? 11. Group 2 on the periodic table corresponds to what family of elements? 12. What family of elements does arsenic (As) belong? 13. What elements are designated as family members of Arsenic? Click on the name of this group located in the color coded key at the top of the page, what is the common property of the elements in this family? 14. Tungsten (W), Copper (Cu), and Iron (Fe) all belong to the same family, whose members are generally used as conductors of electricity. What family is this? 15.In the top right hand corner of your screen check (√) the box next to “Wide.” This will display the periodic table including the Lanthanoid and Actinoid families. Do the Lanthanoid and Actinoid families have specific group numbers? 16. Click on the word Lanthanoid, what is another common name for this group of elements? 17. Click on the word Actinoid, this family of elements are known to be radioactive. What important example, shown in the picture, is given regarding a real-life connection to these elements? 21 18. Complete the following table, by finding the atomic numbers and atomic masses for each element: Symbol Be O Al Ar K Ca Te I Xe Atomic number Atomic Mass a. Using the data in the table above, is the periodic table is organized by increasing atomic mass? Explain. b. What property is the periodic table organized by? *In the top right hand corner of your screen check (√) the box next to “Electrons.” This will make the electron count for each element appear to the right of its symbol in the periodic table. 19. What electron pattern do you notice for all of the elements belonging to the Alkali Metal family? 20. Considering your answer above, though we know Hydrogen is a non-metal, why do you think it is placed on top of the alkali metals? 21. What electron pattern can be observed with the Noble Gases? The Halogens? *Bohr Models can be used to show, roughly, how electrons are arranged in an atom. Recall that the number of electrons is equal to the number of protons in a neutral atom, which is also the same as the atomic number for the element. Bohr Models: The first ring can contain up to 2 electrons The second ring can contain up to 8 electrons The third ring can contain up to 8 electrons The fourth ring can contain up to 2 electrons The Bohr model is completed for a given atom by filling the inner most ring to its capacity and moving outward to each subsequent ring, filling each to its 22 capacity before moving on. Electrons on the outer most ring are known as VALENCE ELECTRONS. These are the electrons that participate in chemical bonding. Each dot represents one electron. 22. Identify the elements shown in the Bohr models below and give the number of valence electrons in each atom: a. b. c. Element= Element= Element= Valence Electrons = Valence Electrons = Valence Electrons = 23. Draw Bohr models for the elements listed below and state the number of valence electrons in each. a. Nitrogen (N) b. Chlorine (Cl) c. Calcium *At the top of your screen check select the to “properties” tab. Next check (√) the box in the center next to “Valence,” this will show the valence electron count for each element appear in the bottom left of its symbol on the periodic table. 24. The transition metal family is very large, which group numbers are included as part of this family? Can you see a pattern for their electron numbers? 23 Activity - Periodic Table Scavenger Hunt Directions Using your computer, tablet or mobile device, navigate to the website: www.ptable.com You will interact with this periodic table to find the answers to the questions below. 1. What color element symbol designates elements that are a gas at a given temperature? 2. What family of elements does the light pink color indicate? 3. Hover the cursor over Magnesium, Mg, what type of specific information is given about the element in the enlarged information area? 4. Now click on the element symbol for Magnesium, Mg. What information are you presented with? 5. What are the element symbols for the Metalloid elements? 6. What is the symbol and atomic number of the element with the most protons according to this periodic table? Click on its symbol to find out what year it was discovered. 7. If an element’s symbol is written in blue, what information does this tell you? 8. Reduce the temperature value to 0K, using the control (shown in the upper right hand side of the screen). How many gaseous elements exist at 0K according to the table? How many liquid elements exist? List the symbol of any elements that fall in these categories. 9. Change the temperature value to room temperature, 298K. At the top of the screen, choose the “Properties” tab. How does this view differentiate between solid, liquid and gas element states? 24 10.Using your cursor, choose Iron, Fe. Determine the following values for Iron: a. Melting Point = b. Boiling Point = c. Atomic Radius = d. Density = 11. A large value for thermal conductivity means that the element is a strong conductor of heat, whereas a small value means the element is a weak conductor. Find the elements that are the strongest and weakest conductors of heat; List their symbol and conductivity value below. (Select “Thermal Conductivity” to make this easier). 12. By specifically selecting any of the properties at the top of the periodic table, you can sort the table by individual details. Highlight the “discovered” option from the list. Can you find an element that was discovered in each of the following years? (Use the slider to help move through time!) a. 1772 = b. 1803 = c. 1900 = d. 2004 = 13. At the top of the screen, choose the “Orbitals” tab. The periodic table is now identified by only four specific sections, what do each of the colors represent? 14. As you move the cursor over the elements, you should see the correct orbital diagram at the top center of the screen for each element, as well as the electron configuration for each element displayed at the top right. What is the electron configuration for Selenium, Se, atomic #34? 15. At the top of the screen, choose the “Isotopes” tab. Click on Copper, Cu, atomic #29. How many isotopes are shown for Copper and what are the abundancies of each? 16. Click on Tellurium, Te, atomic #52. How many isotopes are shown for Tellurium? 25 *Click the “Wikipedia” tab in the top left of the screen, it should produce a drop down menu for you to choose from. Select “Videos.” 17. Choose element #10, neon and watch the short video. a. What color is a “neon light”? b. Where would you see neon used this way in your everyday life? 18. Choose element #37, Rubidium and watch the short video. a. What reaction is conducted with Rubidum? b. What are the results of the reaction? 19.Choose element #16, Sulfur and watch the short video. a. What is the “Barking Dog Experiment?” b. What was a historical use for this reaction years ago? 20.Choose your favorite element, or the element symbol that appears in your written name the most often and watch the short video for it. a. What element did you choose? b. What did you learn about this element? 26 Activity - The Periodic Table Student Information Sheet The Periodic Table is a list of all the known elements. It is organized by increasing atomic number. There are two main groups on the periodic table: metals and nonmetals. The left side of the table contains the metals with the greatest metallic properties. As you move from the left to the right, the elements become less metallic with the far right side of the table consisting of the nonmetals. The elements in the middle of the table are called “transition” elements because their properties change from metallic properties to nonmetallic properties. A small group whose members touch the zigzag line between the metals and nonmetals are called metalloids because they have both metallic and nonmetallic properties. The table is also arranged in vertical columns called “groups” or “families” and horizontal rows called “periods.” Each arrangement is significant. The elements in each vertical column or group have similar properties. The elements in each group have the same number of valence electrons which determines the elements chemical properties including reactivity. The valence electrons are the electrons on the outer most energy level of the atom. There are 18 groups (columns) on the periodic table. They are as follows: Hydrogen: This element does not match the properties of any other group so it stands alone. It is placed above group 1 but it is not part of that group. It is a very reactive, colorless, odorless gas at room temperature. Hydrogen only has one valence electron. Group 1: Alkali Metals – These metals are extremely reactive. They all have 1 valence electron (same as the group #). They are shiny and silver in color. Their density is extremely low so that they are soft enough to be cut with a knife. Group 2: Alkaline-earth Metals – Slightly less reactive than alkali metals. They all have 2 valence electrons (same as the group #). They are silver colored and denser than alkali metals. Groups 3 – 12: Transition Metals – These metals have a moderate range of reactivity and a wide range of properties. In general, they are shiny and good conductors of heat and electricity. They also have higher densities and melting points than groups 1 & 2. These elements have 1 or 2 valence electrons. Lanthanides and Actinides: These are also transition metals that were taken out and placed at the bottom of the table so the table wouldn’t be so wide. The elements in each of these two periods share many properties. The lanthanides are shiny and reactive. The actinides are all radioactive and are therefore unstable. Elements 95 through 103 do not exist in nature but have been manufactured in the lab. Group 13: Boron Group – Contains one metalloid and 4 metals. They are Reactive. These all have 3 valence electrons (group # minus 10) 27 Group 14: Carbon Group – Contains one nonmetal, two metalloids, and two metals. These all have 4 valence electrons (group # minus 10) and have varied reactivity. Group 15: Nitrogen Group – Contains two nonmetals, two metalloids, and one metal. They have varied reactivity. These elements have 5 valence electrons (group # minus 10). Group 16: Oxygen Group – Contains three nonmetals, one metalloid, and one metal. They are a reactive group. These elements all have 6 valence electrons (group # minus 10). Group 17: Halogens – All nonmetals. Very reactive. Poor conductors of heat and electricity. Tend to form salts with metals. Ex. NaCl: sodium chloride also known as “table salt”.) These elements have 7 valence electrons (group # minus 10). Group 18: Noble Gases – Unreactive nonmetals. All are colorless, odorless gases at room temperature. All found in earth’s atmosphere in small amounts. These elements have a full outer energy level, usually 8 valence electrons except for Helium. Helium only has 2 valence electrons. Color Coding the Periodic Table Instructions: 1. Label the groups with 1-18 at the top of each column. 2. Label the periods with 1-7 at the left of each row. 3. Label the groups names (as stated above) at the top of each column. 4. Under each group/family (column), write the number of valence electrons the elements have in that group. Note: Do not include groups 3-12. These are the transition metals. They all have 1 or 2 valence electrons. 5. Draw a “G” in the boxes of the elements that exist as a gas at room temperature. 6. Draw an “L” in the boxes of the elements that exist as a liquid at room temperature. 7. Draw a HEAVY BLACK LINE down the staircase that separates the metals from the nonmetals. 8. Use the following colors to identify the various sections of the periodic table. a. Alkali Metals = red b. Alkaline Earth Metals = brown c. Transition Metals = purple d. All other metals = orange e. Metalloids = blue f. Halogens = green g. Noble Gases = yellow i. All other nonmetals = leave white j. Lanthanide Series = draw a red diagonal line through each element k. Actinide Series = draw a blue diagonal line through each element 9. Make a legend of your color key in the box labeled “key” of your periodic table 28 KEY 29 Color Coding the Periodic Table Related Questions Part 2: Answer the following questions on a separate piece of paper. 1. The vertical columns on the periodic table are called _______________. 2. The horizontal rows on the periodic table are called _______________. 3. Most of the elements in the periodic table are classified as _______________. 4. The elements that touch the zigzag line are classified as _________________. 5. The elements on the right side of the periodic table are classified as________________. 6. Elements in the first group are extremely reactive. They are called ______________ ______________. 7. Elements in groups 3 through 12 have many useful properties and are called _________________ _______________. 8. Elements in group 17 are known as “salt formers”. They are called _________________. 9. Elements in group 18 are very unreactive. They are said to be “inert”. We call these the ______________ ______________. 10. How many elements are in the lanthanide series? ______________________. 11. What is the name of the element in group 3, period 4? ____________________. 12. Pick any element from the periodic table. List all the information about this element based on your color-coded periodic table. ELEMENT: ______________ ______________________________________________________________________ ______________________________________________________________________ 30 Classwork 3-2: 1. Write in the space, “Group 1 metals”, “Group 2 metals”, “transition metals”, “halogens”, or “noble gases” to indicate which group each statement is describing Colored solutions Full valence shell Most active metals Most active nonmetals Monatomic gases Diatomic elements Stable and unreactive 7 valence electrons 2 valence electrons Form ions with a +1 charge a. b. c. d. e. f. g. h. i. j. 2. Describe one chemical property of Group 1 metals that results from the atoms of each metal having only one valence electron. 3. Given: Samples of Na, Ar, As, RB a. Which two of the given elements have the most similar chemical properties? b. Explain your answer in terms of atomic structure. 4. Given: Samples of sulfur, oxygen, and phosphorus c. Which two of the given elements have the most similar chemical properties? d. Explain your answer in terms of atomic structure. 5. Based on the Periodic Table, explain why Na and K have similar chemical properties. 31 PERIODIC TABLE – The Basics 1. The periodic table was originally arranged according to _______________________ 2. Our current periodic table is arranged according to _________________________ 3. The periodic table is essentially divided into two types or categories of elements. Those categories are _________________ and ___________________ 4. The dividing line between these two categories of elements is in the shape of a _________________________ 5. The elements that border or touch this dividing line are referred to as _________________________ 6. Explain why the elements from question #5 have this name: ________________________________________________________________ 7. The first period on the table in which we see transition metals is period _____ 8. The transition metals represent a gradual transition or change from _____________ to ____________________ 9. The most metallic elements on the periodic table are found in the a. upper right b. lower right c. upper left d. lower left 10. The least metallic elements on the periodic table are found in the a. upper right b. lower right c. upper left d. lower left 11. Which of the following is NOT a Group I metal? a. Hydrogen b. Lithium c. Sodium d. Potassium 12. Name the only four groups on the periodic table that qualify as families. ________________________________________________________________ ________________________________________________________________ 32 33 34 35 36 37 38 Atomic Radius Exploration Background 1. Draw a picture to support your written definition of the word “radius.” 2. Let’s assume an atom is shaped like a sphere, what subatomic particles would be found in the center? What subatomic particles would be found around the perimeter? 3. Keeping in mind your answers to questions 1 & 2, in your own words describe the meaning of “atomic radius” *Check your answers before moving on to the next portion of the activity. Directions Using your computer, tablet or mobile device, navigate to the website: www.ptable.com You will interact with this periodic table to find the answers to the questions below. Click the “Properties” tab at the top of the page. Next select “Radius” from the properties listed in the top center of the screen. Finally make sure “Calculated radius” is selected from the options on the right. 1. Complete the following data table: Group 1 element Calculated Radius Value (pm) H Li Na K Rb Cs 39 2. What trend in the data do you observe as you move from the top of the periodic table to the bottom within this group? 3. Does this periodic trend apply to any other group? Briefly investigate the atomic radii values in another group to support your answer. 4. What ideas do you have about the factors that actually contribute to the atomic radius trend within a group? (Revisit your background questions to guide you). 5. Complete the following data table: Period 2 Li Be B element Atomic Radius Value (pm) C N O F Ne 6. What trend in the data do you observe as you move from the left of the periodic table to the right within this period? 7. Using your knowledge of the Bohr model, as well as considering the atomic radius data values collected in question #5, complete the following table. Make sure to consider comparative sizing of each model. Period 2 element Li Be B C N O F Ne Bohr Model 8. Does this periodic trend apply to any other period? Briefly investigate the atomic radii values in another period to support your answer. 40 9. What ideas do you have about the factors that actually contribute to the atomic radius trend within a period? (Think about subatomic particles) 10. Draw a vertical and horizontal arrow next to the periodic table outline below. Point the arrows in the direction that the atomic radius increases. 11.Based on the trend arrows drawn, make a prediction, and place the following elements in ordering of increasing atomic radius (for smallest to largest): Si, Ca, C, F, Cs 12.Check values on www.ptable.com and record the actual values for atomic radius in the table below. Was your prediction from question #11 correct? Element symbol Si Ca C Atomic Radius Value Rank (1-5) 1=smallest 5=largest 41 F Cs 13.Read the following descriptions of two important factors that affect the atomic radius of an atom, then answer the following questions: Electron Shielding Effect: This is due to inner electrons “shielding” the valence electrons from the positive pulling force of the nucleus. As an atom increases its number of electron shells, the shielding effect will increase in turn keeping the valence electrons distanced from the nucleus. Effective Nuclear Charge: This is due to the number of protons in an atom, the more protons the stronger the pulling force of the nucleus will be on the electrons in the atom. a. Revisit your answers for questions 1-4. Using the vocabulary terms given above make a statement about the atomic radius trend within a group on the periodic table. Use two specific elements as examples in your response. b. Revisit your answers for questions 5-9. Using the vocabulary terms given above make a statement about the atomic radius trend within a period on the periodic table. Use two specific elements as examples in your response. 42 Lesson 3: Periodic Table Trends Objective: To describe and explain the reason for periodic trends 1. Atomic Radius = a. Reasons: SHIELDING electrons from inner energy levels shield/block valence electrons from the nuclear charge of the nucleus b. Reasons: C. Ionic Radius NUCLEUS getting HEAVIER (more P & N) e- (remember they are very LIGHT) are being pulled in TIGHTER : 43 2. Ionization Energy = (values for each element listed in Table S) X + energy à X+ + eMetals à Nonmetals à a. Reason: b. Reason: 44 3. Electronegativity: GREEDINESS Electronegativity values range from 0.0 to 4.0 The MOST The LEAST a. Reason: * Shielding b. Reason: § 45 ****YOU NEED TO KNOW THESE TRENDS BUT YOU DO NOT HAVE TO MEMORIZE THEM!!!!! YOU CAN FIGURE THEM OUT USING YOUR PERIODIC TABLE AND TABLE S IN YOUR REFERENCE TABLE THE TRICK….. Example- If you are looking for the trend in electronegativity going across a group: Pick 1 element on the left side of the group and 1 element on the right Look up their values using table S If the values get larger than the trend is increasing; if smaller than trend is decreasing Trend is increasing ****This can be done for any trend going across a period or down a group Practice: What is the trend in ionization energy as you go down a group? 46 4. Reactivity = (*Can NOT compare metals to nonmetals) Metals: (recall: the most reactive metal is FRANCIUM) a. Reason: Increased SHIELDING means VALENCE e- are held less tightly e- LOST more easily increased nuclear CHARGE and MASS pulls more tightly on tiny, negative e- HARDER to remove e(magnet vs. car analogy) b. Reasons: Nonmetals: (recall: the most reactive nonmetal is FLUORINE) a. Reason: Increased SHIELDING HARDER for nucleus to attract more valence e- Increased nuclear CHARGE and MASS EASIER for nucleus to attract more valence e- b. Reason: 5. Metallic & Nonmetallic Character a. Metallic Character Metallic character b. Nonmetallic Character Nonmetallic character 47 Summary of Trends: B Si Ge As Sb 48 Te To determine the trend in a group and period for the following properties: Atomic radius, Electronegativity and Ionization Energy Graph paper, pencil, Reference Table S 49 50 51 52 Classwork 3-3: What are the Trends in the Periodic Table? Below is a portion of the periodic table. In the answer spaces provided in the table, fill in the [1] atomic number, [2] atomic radius, [3] number of shells, and [4] number of outer shell electrons as indicated in the key below. Then, answer the questions that follow. KEY Symbol [1] Atomic Number . . . . . . . . . [2] Atomic Radius . . . . . . . . . . [3] Number of Shells . . . . . . . . [4] Number of Outer Electrons [1] __________ __________ __________ __________ H [1] [2] [2] [3] [3] [4] [4] [1] Li [1] Be [1] B [1] C [1] N [1] O [1] F [1] [2] [2] [2] [2] [2] [2] [2] [2] [3] [3] [3] [3] [3] [3] [3] [3] [4] [4] [4] [4] [4] [4] [4] [4] [1] Na [1] Mg [1] Al [1] Si [1] P [1] S [1] Cl [1] [2] [2] [2] [2] [2] [2] [2] [2] [3] [3] [3] [3] [3] [3] [3] [3] [4] [4] [4] [4] [4] [4] [4] [4] [1] K [1] [2] [2] [3] [3] [4] [4] Ca 53 He Ne Ar Answer the questions below by referring to the data on the table you filled in on the first page. 1. As you go from left to right across a row of the Periodic Table: a. What happens to the atomic number and the number of protons? b. As a result, what happens to the pull on the electrons? c. Therefore what happens to the atomic radius? d. Finally, what does this mean about the likelihood of losing electrons? Do the elements become more or less metallic? 2. As you go from top to bottom down a column of the Periodic Table: a. What happens to the number of shells? b. As a result, what happens to the atomic radius? c. Therefore, what happens to the pull on the electrons? d. Finally, what does this mean about the likelihood of losing electrons? Do the elements become more or less metallic? 3. Based on the analysis above, where do metals tend to be located on the Periodic Table? 4. Based on the analysis above, where do nonmetals tend to be located on the Periodic Table? 5. What do the elements at the extreme right of the Periodic Table have in common? What affect does this have on the chemical properties? 6. Where on the Periodic Table, approximately, is the border between the metals and nonmetals (the metalloids)? 54 55 56 57 58 59 60 61 62 63 Lesson 4: Allotropes Objective: To define and recognize an allotrope Allotropes Elements such as carbon, oxygen, phosphorus, tin and sulfur, display allotropy. The different physical properties displayed by allotropes of an element are explained by the fact that the atoms are arranged into molecules or crystals in different ways. Some allotropes of an element may be more chemically stable than others. Allotropes of Oxygen There are Both allotropes of oxygen are made up only of oxygen atoms, O2 and O3 have different physical properties such as colour, odour, melting and boiling point, density and solubility. Some properties of the allotropes of oxygen are shown below: PROPERTY Structure OXYGEN (O2) OZONE (O3) O=O linear bent Color colorless gas pale blue liquid pale blue solid pale blue gas deep blue liquid deep violet solid Odor odourless sharp, pungent -219 -193 Boiling Point ( C) -183 -111 Density (20oC) 1.3 g/L 2.0 g/L Solubility in Water slightly soluble more soluble that O2 Chemical Stability stable decomposes to O2 easily Uses common oxidizer sterilizing agent it is poisonous to many living things Melting Point (oC) o Allotropes of Carbon The two most common, Both graphite and diamond are made up of carbon atoms, but the arrangement of atoms is different in each allotrope which results in different physical properties. In particular, the presence of delocalized electrons in the structure of graphite results in it being soft and a good electrical conductor whereas diamond is very hard and an electrical insulator. Some properties of graphite and diamond are shown below: 64 PROPERTY Structure GRAPHITE Each carbon atom is bonded to 3 other carbon atoms in layers with delocalized electrons between the layers. DIAMOND Each carbon atom is bonded to 4 other carbon atoms in a 3-dimensional covalent network. All valence electrons are used in bonding. Color black colorless Melting Point (K) sublimes at ~3500 sublimes at ~4000 Electrical Conductivity good delocalized electrons between the layers allow an electric current to pass through poor (an insulator) no delocalized electrons to allow for the flow of electrical current Hardness (Mohs Scale) 1-2 (soft) delocalized electrons allow the sheets to move over each other 10 (hardest known natural mineral) Chemical Stability stable decomposes slowly over time Uses lubricant because it is soft abrasive because it is so hard 65 Classwork 3-4: Unit Reviews Periodic Table Activity - Atoms and Elements INTRODUCTION Primary substances, called elements, build all the materials around you. There are more than 109 different elements known today. The elements are composed of atoms, the smallest units that are characteristic of a particular element. Some elements occur in different forms, such as graphite and diamond for the element carbon. But whatever the form of the element, it is composed of its characteristic atoms. In this experiment, you will be looking at some elements in the laboratory display. Some look different from each other, while others look similar. Elements can be categorized in several ways. In this experiment, you are going to group elements by similarities in their physical properties. Elements that appear shiny or lustrous are called metals. Metals are usually good conductors of heat and electricity, somewhat soft and ductile, and can be molded into a shape. Some of the metals you will see such as sodium or calcium may have an outer coating of a white oxide formed due to combination with oxygen in the air. If cut, you would see the fresh shiny metal underneath. Other elements called nonmetals are not good conductors of heat and electricity, are brittle, and appear dull (not shiny). Atoms are made of even smaller particles of matter called subatomic particles. A large number of subatomic particles are now known, but we are primarily interested in the protons (p), neutrons (n), and electrons (e). Protons are positively charged particles (+1), electrons are negatively charged particles (–1), and neutrons are neutral (charge = 0). The charge is often included with the symbol: p+, n0, and e–. Within the atom, the protons and neutrons are tightly packed together in the nucleus and are collectively called “nucleons.” Moving electrons outside of the nucleus occupy the rest of the atom, which is mostly empty space. Electrons are so small that their mass is almost negligible compared to the mass of the protons and neutrons in the nucleus. Atoms of a particular element have one feature in common: the number of protons in the nucleus. The number of protons, called the atomic number (Z) is unique for each element. Atoms of the element hydrogen always have one proton in their nuclei, while atoms of the next element, helium, always have two protons in their nuclei. Atoms of the element carbon similarly contain six protons, and atoms of iron have 26 protons. The sum of the number of protons and neutrons in the nucleus of an atom is called the mass number (A) of the atom (remember A for “all”): Mass Number = Number of Protons + Number of Neutrons Protons attract the electrons because they have opposite charges. In a neutral atom, the number of protons is equal to the number of electrons. This is the normal situation in atoms. However, through chemical reactions, an imbalance in the number of protons and electrons can result. For example, when the element sodium (11p+, 11e–) reacts with the element chlorine (17p+, 17e–) the compound sodium chloride, NaCl, is formed. Sodium chloride is an ionic compound composed of sodium ions, Na+, with +1 charges, and an equal number of chloride ions, Cl–, with –1 charges. In the reaction, each sodium atom loses one electron and each chlorine atom gains one electron, so the number of protons and electrons are now 11p+, 10e– in the Na+ ion and 17p+, 18e– in the Cl– ion. 66 All neutral atoms of the same element have the same number of protons and electrons, but interestingly, they often differ in the number of neutrons. This means that atoms of the same element while having the same atomic number can have different mass numbers. The atoms of an element that have different numbers of neutrons are called isotopes of that element. In the complete chemical symbol or atomic notation of an element, the mass number and atomic number are indicated next to the symbol. For example, the isotope of the element sodium that has 12 neutrons has the following symbol: The number of protons in an atom (and the number of electrons if the atom is neutral) is given by the atomic number. To determine the number of neutrons, the mass number of the atom is needed. The number of neutrons is determined by subtracting the atomic number from the mass number, A – Z. The Periodic Table The periodic table is a listing, in chart form, of the known elements. It has gone through many revisions and sometimes appears in alternate forms, but with the discovery of atomic numbers in the early 20th century, this has been the basis for the order of the elements in the table. But even before this time, it was long recognized that certain elements shared similar properties, and when the property, such as density, was plotted against atomic mass, a repeating, or “periodic” pattern was observed. Beginning with Dmitri Mendeleev in 1869, chemists began organizing the elements in rows and columns in an attempt to explain the periodic nature of various physical and chemical properties of the elements. Below are shown an early table of Mendeleev’s and a modern periodic table: The modern periodic table is arranged in horizontal rows (also called periods) and vertical columns called groups or families. The rows are numbered from 1 to 7. The groups have not always been numbered consistently, but are usually numbered 1A, 2A, 3A, etc., from left to right, excluding the groups of the transition elements in the middle, which have a different numbering. Because of this confusion, most modern tables have the groups numbered 1 through 18, excluding the lower, separate rows of elements (the lanthanides and actinides) below the main table. 67 Below is a table with the common names of different sections and columns given: The alkali metals, found in Group 1 (or 1A) of the periodic table are very reactive metals and as such do not occur freely in nature. They are the elements Li, Na, K, Rb, Cs, and Fr. The alkaline earth elements are metallic elements found in the second group of the periodic table. They are not as reactive as the alkali metals, but are so reactive that they are likewise never found free in nature. These are the elements Be, Mg, Ca, Sr, Ba, and Ra. The elements of Group 17 (7A) are called the halogens, which mean "salt formers." These are the elements F, Cl, Br, I, and At. The noble gases are found in group 18 of the periodic table. These elements were considered to be chemically inert until the 1960's when their first compounds were characterized. The representative elements occur in Groups 1-2 and 13-18 and exclude the transition metals and inner transition metals. The term "transition elements" most commonly refers to the "d-block" elements in which the d electronic sublevel is being filled with electrons. The "inner transition elements" are the "f-block" elements in which the f-sublevel is being filled with electrons. The inner transition metals are further divided into the lanthanide series and the actinide series. They are normally separated from the rest of the elements in the periodic table in order to save space. 68 For this experiment a laboratory display of the elements and a wall periodic table is required. Part I. Comparison of Physical Properties of Elements Complete the table in the report form by writing the name and atomic number for each element. Observe the elements in the laboratory display. Describe their properties (color and luster). From your observations, describe each type of element as a metal or a non-metal Part II. Predicting Properties Based on Location in the Periodic Table Use the location of the given elements in the periodic table to predict whether the elements listed would be a metal or non-metal and shiny or dull. After you have completed your predictions, observe those same elements in the posted periodic table to determine if you predicted their properties correctly. Part III. Subatomic Particles and Chemical Symbols (a) Complete the table given in the report form with the correct atomic numbers, mass numbers, and number of protons, electrons, and neutrons for the neutral atom of each element. (b) Complete the table with the number of protons, electrons, neutrons, and complete chemical symbol (showing the mass number and atomic number) for each neutral atom. Part IV. Graphing a Periodic Property For this part of the experiment you will make a graph of a periodic property vs. atomic number. The property chosen is atomic radius, given in pm (1 pm = 10–12 m). The atomic radius, r, is related to the volume of the atom by the formula of a sphere, V = 4/3 π r3. In Table 1 below, the atomic radii of the first 54 elements are given. Plot the points on the accompanying graph paper. Label selected “tick mark” values on each axis to make each scale clear. For the atomic radius scale (the Y-axis), 10 pm per mark will work well. Connect the points and note where the high and low parts of your pattern occur in the periodic table. Does your graph indicate a reason for beginning and ending each row of the periodic table at certain elements? Why are the rows of the periodic table called “periods”? 69 Table 1. Atomic Radii of the First 54 Elements From http://www.periodictable.com/Properties/A/AtomicRadius.an.html Atomic Element Number H 1 He 2 Li 3 Be 4 B 5 C 6 N 7 O 8 F 9 Ne 10 Na 11 Mg 12 Al 13 Si 14 P 15 S 16 Cl 17 Ar 18 K 19 Ca 20 Sc 21 Ti 22 V 23 Cr 24 Mn 25 Fe 26 Co 27 Atomic Radius, pm 53 31 167 112 87 67 56 48 42 38 190 145 118 111 98 88 79 71 243 194 184 176 171 166 161 156 152 Atomic Element Number Ni 28 Cu 29 Zn 30 Ga 31 Ge 32 As 33 Se 34 Br 35 Kr 36 Rb 37 Sr 38 Y 39 Zr 40 Nb 41 Mo 42 Tc 43 Ru 44 Rh 45 Pd 46 Ag 47 Cd 48 In 49 Sn 50 Sb 51 Te 52 I 53 Xe 54 70 Atomic Radius, pm 149 145 142 136 125 114 103 94 88 265 219 212 206 198 190 183 178 173 169 165 161 156 145 133 123 115 108 Name ______________________________ Date _________________ Part I Symbol Element Atomic Number Color Shiny/Dull Metal/Nonmetal Zn ………….. …….. …….. …….. ………. Al ………….. …….. …….. …….. ………. Mg ………….. …….. …….. …….. ………. Pb ………….. …….. …….. …….. ………. O ………….. …….. …….. …….. ………. C ………….. …….. …….. …….. ………. Sn ………….. …….. …….. …….. ………. I ………….. …….. …….. …….. ………. Fe ………….. …….. …….. …….. ………. S …………… …….. …….. …….. ………. Hg ………….. …….. …….. …….. ………. Ca ………….. …….. …….. …….. ………. Cu ………….. …….. …….. …….. ………. 71 Part II Element Metal/Nonmetal Shiny/Dull Osmium (Os) ………. ………. Cadmium (Cd) ………. ………. Phosphorus (P) ………. ………. Radium (Ra) ………. ………. Seaborgium (Sg) ………. ………. (predicted) Part III (a) Element Symbol Atomic Number Mass Number Protons Electrons Neutrons F …….. 19 …….. …….. …….. …….. …….. …….. …….. 19 20 Br …….. 80 …….. …….. …….. …….. 79 197 …….. …….. …….. …….. …….. 127 …….. 53 …….. Part III (b) Chemical Symbol Protons Electrons Neutrons …….. …….. …….. …….. …….. …….. …….. 20 …….. 20 …….. …….. 19 22 …….. 17 …….. 20 39 19 K 32 16 S 72 Part IV 73 1. Define the following terms: a) Nucleon b) Transition Element 2. Compare mass, charge, and location of the subatomic particles in the atom. Particle 3. Mass Charge Proton ____________ ______ _____________________ Neutron ____________ ______ _____________________ Electron ____________ ______ _____________________ Describe the location (group and period) of the following metals and nonmetals on the periodic table. Element 4. Location Group Period I _____ _____ Fr _____ _____ Kr _____ _____ Write the complete chemical symbol (including the mass number, atomic number, and charge if any) of the element that corresponds to the following subatomic particles: a) p =1, e = 1, and n = 0 b) p = 36, e = 36, and n = 48 c) p = 26, e = 23, and n = 30 d) p = 35 , e = 36, and n = 44 74 1. Define the following terms: a) Isotopes b) Subatomic particle 2. Compare the physical properties of metals and nonmetals (at least four properties). 3. Use the periodic table to categorize the following elements as metals (M) or nonmetals (NM). S …….. P …….. Cr …….. Ni …….. Sr …….. I …….. 4. A neutral atom has a mass number of 58 and contains 30 neutrons. Write its complete chemical symbol (showing the mass number and atomic number). 5. Determine the number of protons, electrons, and neutrons in the following atoms: Aluminum-27 Bromine-80 Uranium-238 75 Unit 3 Practice Test 1 A diatomic element with a high first ionization energy would most likely be a 12 A solid element that is malleable, a good conductor of electricity, and reacts with oxygen is classified as a A) nonmetal with a high electronegativity B) nonmetal with a low electronegativity C) metal with a high electronegativity D) metal with a low electronegativity 2 The metalloids that are included in Group 15 are antimony (Sb) and A) metal B) metalloid C) noble gas D) nonmetal 13 An atom of lithium-7 has an equal number of A) electrons and neutrons B) electrons and protons C) positrons and neutrons D) positrons and protons 14 Which element has the highest melting point? A) N B) P C) As D) Bi 3 Which represents the electron configuration of a metalloid in the ground state? A) 2-3 B) 2-5 C) 2-8-5 D) 2-8-6 4 The elements of the Periodic Table are arranged in horizontal rows according to each successive element's greater A) atomic mass B) atomic radius C) number of protons D) number of neutrons 5 How many Group 17 elements are in Period 3 of the Periodic Table? A) 1 B) 2 C) 3 D) 4 6 Which sequence of atomic numbers represents elements which have similar chemical properties? A) 19, 23, 30, 36 B) 9, 16, 33, 50 C) 3, 12, 21, 40 D) 4, 20, 38, 88 7 Alkali metals, alkaline earth metals, and halogens are elements found respectively in Groups A) 1, 2, and 18 B) 2, 13, and 17 C) 1, 2, and 14 D) 1, 2, and 17 8 Which element exists as a diatomic molecule at STP? A) bromine B) argon C) sulfur D) rubidium 9 The element in Period 2 with the largest atomic radius is A) a halogen B) a noble gas C) an alkali metal D) an alkaline earth metal 10 Which of the following elements in Period 3 has the greatest metallic character? A) Ar B) Si C) Mg D) S 11 In the formula XF2, the element represented by X can be classified as a A) Group 1 metal C) Group 1 nonmetal B) Group 2 metal D) Group 2 nonmetal A) tantalum B) rhenium C) osmium D) hafnium 15 Atoms of metallic elements tend to A) gain electrons and form negative ions B) gain electrons and form positive ions C) lose electrons and form negative ions D) lose electrons and form positive ions 16 Which element is considered malleable? A) gold B) hydrogen C) sulfur D) radon 17 Which statement describes a chemical property of iron? A) Iron can be flattened into sheets. B) Iron conducts electricity and heat. C) Iron combines with oxygen to form rust. D) Iron can be drawn into a wire. 18 Which element is malleable and ductile? A) S B) Si C) Ge D) Au 19 The least active metal of those represented below has an electron configuration abbreviated as A) 2-8-2 B) 2-8-8-2 C) 2-8-18-8-2 D) 2-8-18-18-2 20 Which element is a liquid at STP and has low electrical conductivity? A) silver B) mercury C) barium D) bromine 21 Which characteristics describe most nonmetals in the solid phase? A) They are malleable and have metallic luster. B) They are malleable and lack metallic luster. C) They are brittle and have metallic luster. D) They are brittle and lack metallic luster. 22 Which gaseous element has the greatest density at STP? A) N2 76 B) O2 C) Cl 2 D) F2 23 The table below shows some properties of elements A, B, C, and D. Which element is most likely a nonmetal? A) A B) B C) C 24 Which statement explains why neon is a Group 18 element? D) D 30 Lithium and potassium have similar chemical properties because the atoms of both elements have the same A) Neon is a gas at STP. B) Neon has a low melting point. C) Neon atoms have a stable valence electron configuration. D) Neon atoms have two electrons in the first shell. 25 Which of the following gases is monatomic at STP? A) mass number B) atomic number C) number of electron shells D) number of valence electrons 31 An atom of an element has 28 innermost electrons and 7 outermost electrons. In which period of the Periodic Table is this element located? A) hydrogen B) chlorine C) oxygen D) helium 26 Pure silicon is chemically classified as a metalloid because silicon A) is malleable and ductile B) is an excellent conductor of heat and electricity C) exhibits metallic and nonmetallic properties D) none of the above 27 Which period contains elements that are all gases at STP? A) 1 B) 2 C) 3 D) 4 28 An atom in the ground state contains a total of 5 electrons, 5 protons, and 5 neutrons. Which Lewis electron-dot diagram represents this atom? A) B) C) D) 29 Which Lewis electron-dot diagram is correct for a S 2– ion? A) B) C) D) A) 5 B) 2 C) 3 D) 4 32 Which is a common characteristic of the elements Rb, Te, I, and Xe in the ground state? A) They have the same number of valence electrons. B) They have similar chemical properties. C) They have electrons occupying the same number of principal energy levels. D) They have completely filled principal energy levels. 33 Which compound forms a green aqueous solution? A) RbCl B) CaCl2 C) NiCl 2 D) ZnCl2 34 Which elements contain atoms that form colored ions and have more than one positive oxidation state? A) alkali metals B) alkaline earth metals C) noble gases D) transition elements 35 Which particle has the same electron configuration as a potassium ion? A) fluoride ion C) neon atom 77 B) sodium ion D) argon atom 36 Which changes occur as a cadmium atom, Cd, becomes a cadmium ion, Cd2+? 41 Atoms of which of the following elements have the strongest attraction for electrons? A) The Cd atom gains two electrons and its radius decreases. B) The Cd atom gains two electrons and its radius increases. C) The Cd atom loses two electrons and its radius decreases. D) The Cd atom loses two electrons and its radius increases. 37 When an atom loses an electron, the atom becomes an ion that is A) aluminum B) chlorine C) silicon D) sodium 42 Atoms of which element have the weakest attraction for electrons? A) positively charged and gains a small amount of mass B) positively charged and loses a small amount of mass C) negatively charged and gains a small amount of mass D) negatively charged and loses a small amount of mass 38 As the elements in Period 2 of the Periodic Table are considered in succession from left to right, there is a decrease in atomic radius with increasing atomic number. This may best be explained by the fact that the A) number of protons increases, and the number of shells of electrons remains the same B) number of protons increases, and the number of shells of electrons increases C) number of protons decreases, and the number of shells of electrons remains the same D) number of protons decreases, and the number of shells of electrons increases 39 As the elements of Group 16 are considered in order from top to bottom, the covalent radius of each successive element increases. This increase is primarily due to an increase in A) atomic number B) mass number C) the number of protons occupying the nucleus D) the number of occupied electron shells 40 An atom with the electron configuration 2-8-2 would most likely A) B) C) D) A) Na B) P C) Si D) S 43 Which atom in the ground state requires the least amount of energy to remove its valence electron? A) lithium atom B) potassium atom C) rubidium atom D) sodium atom 44 Which general trend is found in Period 2 on the Periodic Table as the elements are considered in order of increasing atomic number? A) decreasing atomic mass B) decreasing electronegativity C) increasing atomic radius D) increasing first ionization energy 45 Which sequence correctly places the elements in order of increasing ionization energy? A) H ® Li ® Na ® K B) I ® Br ® Cl ® F C) O ® S ® Se ® Te D) H ® Be ® Al ® Ga 46 As the Group 1 elements of the Periodic Table are considered from top to bottom, the first ionization energy of each successive element decreases. One reason for this is that the A) B) C) D) nuclear charge is decreasing number of neutrons is increasing number of principal energy levels is decreasing distance between the valence electron and the nucleus is increasing 47 Which element has an atom in the ground state with the most loosely bound electron? A) He B) As C) Xe D) Cs 48 In which group of the Periodic Table do most of the elements exhibit both positive and negative oxidation states? A) 17 decrease in size as it forms a positive ion increase in size as it forms a positive ion decrease in size as it forms a negative ion increase in size as it forms a negative ion 78 B) 2 C) 12 D) 7 49 The graph below represents the relationship between atomic radii, in picometers, and increasing atomic number for elements in Group 15. Which element is most metallic A) A B) B C) D D) E 50 When the elements in Group 1 are considered in order from top to bottom, each successive element at standard pressure has A) B) C) D) a higher melting point and a higher boiling point a higher melting point and a lower boiling point a lower melting point and a higher boiling point a lower melting point and a lower boiling point 79 Unit Review: Periodic Table Place a checkmark next to each item that you can do! If a sample problem is given, complete it as evidence. _____1. I can still do everything from Unit 1A. _____2. I can still do everything from Unit 1B. _____3. I can still do everything from Unit 2. Classify each of the following elements as metals (M), nonmetals (NM), or metalloids (MTLD). _____4. I can classify elements as metals, nonmetals, or metalloids based on their placement on the Periodic Table. _______B ________K ________Li ________C _______Ar _______Sb ________H ________Fe ________Au _______S _______F ________Si ________Fr ________He _______Rn _______Ge ________Al ________As ________Bi _______I Group 1 is called the ____________________________________. _____5. I can state the group names for elements in groups 1, 2, 17, and 18. _____6. I can explain why elements in the same group have similar chemical properties. _____7. I can explain why the elements in Group 18 don’t usually react with other elements. _____8. I can state the meaning of “STP” and the Reference Table on which it can be found. _____9. I can state the names/symbols for the two elements on the Periodic Table that are liquids at STP. Group 2 is called the ____________________________________. Group 17 is called the ____________________________________. Group 18 is called the ____________________________________. Elements in the same group have similar chemical properties because Elements in Group 18 don’t usually react with other elements because STP stands for ____________________________________________________. The values can be found on Reference Table______________. The two elements that are liquids at STP are: ________________________ and __________________ 80 The 11 elements that are gases at STP are: _____________________________, _______________________________, _____________________________, _______________________________, _____10. I can state the names/symbols of the 11 elements that are gases at STP. _____________________________, _______________________________, _____________________________, _______________________________, _____________________________, _______________________________, and _____________________________ _____11. I can state how the elements on the Periodic Table are arranged. The elements on the Periodic Table are arranged by increasing _______________ ____________________. The seven diatomic elements are: _____12. I can list the 7 diatomic elements. Definitions: electronegativity first ionization energy atomic radius _____13. I can define electronegativity, first ionization energy, atomic radius, ionic radius, metallic character, and activity/reactivity. ionic radius metallic character activity/reactivity 81 As one reads down a group from top to bottom, electronegativity ______________________ because __________________________________ _____14. I can state the periodic trend for electronegativity and explain why it occurs. ______________________________________________________________. As one reads across a period from left to right, electronegativity ______________________ because __________________________________ ______________________________________________________________. As one reads down a group from top to bottom, first ionization energy _____17. I can state the periodic trend for first ionization energy and explain why it occurs. ______________________ because __________________________________ ______________________________________________________________. As one reads across a period from left to right, , first ionization energy ______________________ because __________________________________ _____________________________________________________________. As one reads down a group from top to bottom, atomic radius ______________________ because __________________________________ _____15. I can state the periodic trend for atomic radius and explain why it occurs. ______________________________________________________________. As one reads across a period from left to right, atomic radius ______________________ because __________________________________ ______________________________________________________________. As one reads down a group from top to bottom, metallic character _____16. I can state the periodic trend for metallic character and explain why it occurs. ______________________ because __________________________________ ______________________________________________________________. As one reads across a period from left to right, metallic character ______________________ because __________________________________ ______________________________________________________________. 82 _____17. I can state the trend for melting points and boiling point for METALS as one reads down a group. _____18. I can state the trend for melting points and boiling point for NONMETALS as one reads down a group. As one reads down a group from top to bottom, the melting points and boiling points for METALS ______________________. As one reads down a group from top to bottom, the melting points and boiling points for NONMETALS ______________________. 83 _____19. I can state the trend for activity/reactivity for METALS as one reads down a group. _____20. I can state the trend for activity/reactivity for NONMETALS as one reads down a group. As one reads down a group from top to bottom, the activity/reactivity of METALS ____________________. As one reads down a group from top to bottom, the activity/reactivity of NONMETALS ____________________. Metals tend to lose electrons (get oxidized). This loss of electrons causes _____21. I can explain how loss or gaining of electrons affects the radius of an element. cations to be __________________ than the original atom. Nonmetals tend to gain electrons (get reduced). This gain of electrons causes anions to be __________________ than the original atom. Properties of metals are: _____22. I can list the properties of metals. Properties of non metals are: _____23. I can list the properties of nonmetals. 84