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SNC2D1 CHEMISTRY REVIEW OF GRADE 9 CONCEPTS CLASSIFICATION OF MATTER ______________ Takes up space and mass __________ SUBSTANCE Made up of components not found on the Periodic Table _______________ MIXTURE Two or more phases Non-uniform composition _______ SUBSTANCE Made up of components found on the Periodic Table Always contain one phase (HOMOGENEOUS) _______________ MIXTURE One phase Uniform composition _____________ Only one particle Can not be broken down further _____________ Contains two or more elements WHAT IS THE PERIODIC TABLE OF ELEMENTS? The Periodic Table of elements classifies elements and groups them according to characteristics such as _____________, ________________ and _________________. The horizontal rows of the Periodic Table are called ____________ and there are ____ periods on the Periodic Table Elements of a period have _____________ properties SNC2D1 The vertical columns of the Periodic Table are called ____________ or ____________ and there are _____ Groups on the Periodic Table Elements in the same group have the __________ number of electrons on the ____________ orbital/shell The existing elements are separated into ____ different categories: _______________ – Conduct electricity well _______________ – Do not conduct electricity Insulators ________________ (also known as SEMI-METALS) – Has properties of both metals and non-metals Some groups have a special name Group 1 ____________________ Highly reactive metals Group 2 ________________________ Less reactive metals than Group 1 Group 3 – 12 ______________________ Some metallic properties Group 17 __________________ Highly reactive non-metals Group 18 _________________________ Very unreactive gases And __________________ Gas at room temperature SNC2D1 WHAT IS AN ATOM? Atoms are ________________________________________________________ The Bohr - Rutherford model of the atom is often referred to as the “solar system model” Using a Venn diagram, compare the atom to our solar system. Inside the atom, three particles exist: ______________ _______________ ______________ Found inside the ____________ of the atom Found “orbiting” the nucleus in paths called ______________ Found in the _________ of the atoms Has a charge of _____ Charge of _____ Charge of zero Mass= ________ amu Mass= ________ amu Mass= ________ amu SNC2D1 DRAWING ATOMS (BOHR-RUTHERFORD DIAGRAMS) For any atom, we can use information provided by the periodic table to help us draw Bohr-Rutherford Diagrams. To draw a correct diagram, the occupancy rules must be known. What are the maximum number of electrons allowed in each energy level? 1st : max ___ electrons 2nd : max ___ electrons P N 3rd : max ___ electrons In addition, one must be able to determine the number of protons, electrons and neutrons using an atom’s atomic number and mass number. 13 Al 27 ATOMIC NUMBER = # OF ____________ and the # OF _______________ MASS NUMBER is the number of ______________ + _______________ # OF NEUTRONS = ___________________ – ____________________ Identify the element above this box and determine it’s number of protons, electrons and neutrons. What are the rules for placing electrons in a Bohr-Rutherford diagram? (3) SNC2D1 EXAMPLE Drawing the Bohr-Rutherford Diagram for Aluminum Number of protons = ______ 13 Al 27 Number of electrons = ______ Number of neutrons = _______________ = ________ WHAT ARE VALENCE ELECTRONS? Valence electrons are _____________________________________________ When valence electrons are present, an atom can _______ or ________ electrons, depending how many electrons it requires to become ____________ WHAT ARE IONS? All atoms are ___________ until they ________ or __________ electrons. [Recall that neutral atoms have the _________ number of protons and electrons] When an atom gains an electron, there are _________ electrons than protons and a _____________ ion is created (also known as an ANION) When an atom loses an electron, there are _________ electrons than protons and a _____________ ion is created (also known as a CATION) Practice Questions: pg 148 #3, 4a; pg 149 #1; pg 150 #1-3; pg 153 #3, 10, 11 SNC2D1 PHYSICAL AND CHEMICAL PROPERTIES Chemistry relates the properties of substances to the structure of the particles that make up those substances. By recognizing and applying patterns in chemistry ______________________ _______________________________________________________________ Properties of substances are important because they determine what the _________________________ and help scientists _____________________. Physical properties are those that can be observed without chemically changing a substance. Chemical properties are those observed when a substance undergoes a ________________________. GROUP ACTIVITY: OBSERVING THE PROPERTIES OF MATTER Consider three of the alkali metals; lithium, sodium and potassium. What are some physical properties that these elements have in common? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ What other physical properties could be determined for these substances? ____________________________________________________________________ ____________________________________________________________________ To observe chemical properties we must allow the metals to chemically react. Let’s observe and describe some of their chemical properties. 1. Reaction with air ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 2. Reaction with water ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ Common chemical properties include (p. 142): _________________________________ _______________________________________________________________________ master SNC2D1 Atomic Structure and Properties Atoms of the same group (family) have very similar properties (chemical and physical) In terms of atomic structure, what is common about the alkali metals involved in the demo? (see page 150, figure 4.17) _________________________________________________________________ _________________________________________________________________ What do you recall about the chemical properties of the noble gases? _________________________________________________________________ What is common about their atomic structure? _________________________________________________________________ The __________________________________ within an atom plays a big part in determining the properties of an element. Periodic Pattern: # of valence electrons group v-electrons 1 2 13 14 15 16 17 18 Lewis Symbols These are a more convenient method of communicating the valence structure of an atom. (These will be handy later when we learn about covalent bonding.) Rules: ______________________ ______________________ ______________________ ______________________ Example: phosphorous Draw Lewis symbols for an element from group 1, 13, 16 and 18. Groups 3 – 12 These elements follow a different and more complicated set of rules. We generally ignore discussing their specific atomic structures until later courses. Atom Builder: http://www.sciencesource2.ca/resources/flt_atom_builder.swf Element Builder: www.explorelearning.com SNC2D1 KNOWLEDGE CHECK 1. Identify the element that lives in … a) group 2 and period 3. b) Period 4 and has 7 valence electrons. 2. How many electrons are allowed in the 2nd energy level? 3. What is a chemical property that is shared be all alkali metals? 4. Write the Lewis symbol for … a) nitrogen b) iodine 5. Initially two or more elements were placed in the same group of the periodic table because ? 6. How many neutrons does Uranium have? 7. Which section of the periodic table contains … a) elements that conduct electricity? b) Some gaseous elements? 8. The following diagram was drawn to show the electrons in boron. What is wrong? SNC2D1 THE QUEST FOR NOBILITY Ions Ions are atoms or “molecules” that carry a charge because the number of protons does not equal the number of electrons. An atom becomes an ion when it _________________________ electrons. Atoms that lose electrons become ___________ ions (cations) Atoms that gain electrons become ___________ ions (anions) Explaining Ion Formation Based on patterns, it seems that atoms lose/gain electrons such that their electron structure matches their closest ______________________ neighbor. Consider sulphur, As an atom it has ___ protons and ___ electrons. The ion of sulphur has 16 protons and 18 electrons (like ____________). In gaining 2 electrons, the charge on a sulphide ion would be _______. The symbol for a sulphide ion is _______. Periodic Pattern for ion charge group charge 1 2 3 14 15 16 17 18 Ion Nomenclature 1. Metals – add roman numerals that equal charge if multivalent*. Otherwise use elemental name unchanged. 2. Non-metals – change ending to “ide” *multivalent metals – those that can have more than one charge. Examples, K+ - potassium ion; N-3 – nitride ion; Cu+ - copper (I) ion (multivalent) – Do Page 158 #1,2 – Choose five other elements and write the symbol and name for their ions SNC2D1 IONIC COMPOUNDS Recall – compounds are pure substances that contain more than one type of element that are bonded together in a fixed ratio. Water (H2O) is an example of a compound. In water, the two hydrogen atoms are stuck to the oxygen and can’t be separated without undergoing a chemical change. There are two types of compounds; Ionic and Covalent. Ionic Compound – A compound consisting of negatively and positively charged ions held together ionic bonds. (ionic bonds – force of attraction between two oppositely charged ions, opposites attract). Binary Ionic Compounds These involve metal ions (+) bonded to non-metal ions (-). The ratio of the ions to each is such that the total charge of the compound is ________. This ratio is shown in the ___________________ of a compound. e.g. Naming these compounds is easy. Simply name the metal ion (with roman numerals if needed) and then the non-metal ion (‘ide’). All letters should be lower case. Ionic Compounds with Polyatomic Ions Some ions are polyatomic (multi-atom ions). Most of these are negative. Some common ones are in table 4.7 on page 161. Copy these on the back of your periodic table. e.g. The subscripts in these ions cannot be changed except through some chemical reactions. Writing formulas for these follows the same rules as for binary compounds. Total charge = 0! e.g. Naming these compounds is also easy. How do you know a polyatomic ion is involved when looking at a chemical formula/chemical name? page 159 #1-4; page 160 #1-4; page 161 #1-4; page 163 #1-4; page 164 #1-4 SNC2D1 Chemistry: Ions in Chemical Compounds Complete the following table by writing a formula so that the total charge on the resulting compound is zero. Also write the name for each compound. Ions Hydroxide Cl1- Carbonate Sulfate NO31- Hydrogen H1+ Sodium Na1+ Ammonium NH41+ Potassium K1+ Calcium Ca2+ Magnesium Mg2+ Aluminum Al3+ Iron (II) Fe2+ Iron (III) Fe3+ Pb2+ Tin (IV) Cu1+ Copper (II) Ionic Bond Gizmo: www.explorelearning.com S2- PO43- SNC2D1 MOLECULAR COMPOUNDS (COVALENT) Some atoms achieve a ______________ electron structure by sharing electrons with another element. The mutual attraction that each atom has for the shared electrons is called a ___________________. One covalent bond consists of 2 shared electrons. Generally, covalent bonds exist between __________________ elements. A structure that consists of two or more covalently bonded atoms is called a ___________________. Perhaps the simplest molecules are the diatomic elements such as H2. The bonding that holds an H2 molecule together can be illustrated using Lewis structures or structural diagrams which are derived from Lewis Symbols. Rough Work using Lewis symbols Lewis Structure Structural Diagrams Illustrating the bonding in O2 and N2; Rough Work using Lewis Lewis Structure symbols Structural Diagrams SNC2D1 What about molecules containing different atoms? Consider HCl. Rough Work using Lewis symbols Lewis Structure Structural Diagrams Single bond – ____ shared electrons between two atoms Double bond – ____ shared electrons between two atoms Triple bond – ____ shared electrons between two atoms Naming Molecular Compounds Prefix Method is used prefix 1 2 3 4 5 6 7 8 If the compound your naming contains two different non-metal elements it is a molecular compound!! Simply name the first element followed by the second, each with a prefix indicating how many of each element are in a molecule. Annoying Rule – If there is only one of the first element, do not use a prefix for it. If there is only one of the second element, you must use a prefix. Examples Questions: page 168 # 1-4 (top and bottom); page 171 # 6-10, 12-13 Do molecular modeling activity on page 170 Covalent Bond Gizmo: www.explorelearning.com SNC2D1 PERIODIC TABLE COLOUR CODING Colour code your periodic table so that it identifies the following; • • • • • • • • • • • • Alkali metals Alkaline earth metals Halogens Noble gases Metals Non-metals Transition metals Semi-metals (metalloids) Liquid elements Gaseous elements Diatomic elements Multivalent metals (no non-metals) Be sure to make a legend. You may want to do this on a separate piece of paper. Use pages 146 - 148 and page 165 (table 4.11) in your text as a reference. You will be allowed access to this periodic table for your next test. Please do not add any other information unless asked to do so. PERIODIC TABLE COLOUR CODING Colour code your periodic table so that it identifies the following; • • • • • • • • • • • • Alkali metals Alkaline earth metals Halogens Noble gases Metals Non-metals Transition metals Semi-metals (metalloids) Liquid elements Gaseous elements Diatomic elements Multivalent metals (no non-metals) Be sure to make a legend. You may want to do this on a separate piece of paper. Use pages 146 - 148 and page 165 (table 4.11) in your text as a reference. You will be allowed access to this periodic table for your next test. Please do not add any other information unless asked to do so. Periodic Table SNC2D1 Review compounds flow chart.doc naming compounds relay.doc http://www.learner.org/interactives/periodic/basics_interactive.html Quiz #1 – written Quiz #1 – m/c SNC2D1 CHEMICAL REACTIONS PHYSICAL VS. CHEMICAL CHANGES 2DCHEM_-_WS_3_(Changes_in_Matter_Concept_Map).pdf CHEMICAL REACTIONS 2minute video animated chemical reaction REPRESENTING CHEMICAL REACTIONS USING EQUATIONS A chemical equation is an efficient method of communicating what happens in a particular chemical reaction. When magnesium is ignited in the presence of oxygen it burns to produce solid magnesium oxide. word equation: magnesium + oxygen → magnesium oxide (reactants) (products) chemical equation: Mg(s) + O2(g) → MgO(s) • In a skeletal equation, the states of matter are often communicated in brackets behind each reactant and product. (s) – solid (v) - vapour (l) – liquid (aq) – aqueous (dissolved in water) (g) - gas **Remember the diatomic elements (7-up) Page 175 #1-5; page 187 #4; handout THE LAW OF CONSERVATION OF MASS THE TOTAL MASS DURING A CHEMICAL REACTION CANNOT CHANGE TOTAL MASS OF REACTANTS = TOTAL MASS OF PRODUCTS ALL ATOMS MUST BE ACCOUNTED FOR IN A CHEMICAL REACTION SNC2D1 Examples; 1. 5 grams of chemical A reacts with 7 grams of chemical B to produce chemical C. a) What is the equation? A + B → C b) What mass of C must have been produced? A + B → C 5g 7g ?g 12g = 12g (LCM) ** 12 grams of C must have been produced. 2. How much of chemical X must have been added to 4 grams of chemical Y to produce 7 grams of chemical Z? Word equation: Masses: Total Mass: Missing mass: X + Y → Z ?g 4g 7g 7g 7g X=7–4=3g http://www.saskschools.ca/curr_content/science10/unitb/lawmasqs.html BALANCING CHEMICAL EQUATIONS Task – place an appropriate coefficient in front of each reactant or product to ensure that all atoms are conserved. Rule – you may only change coefficients. Subscripts cannot be changed as this would change the identity of a reactant or product. Page 187 #5,6 Counting Atoms Worksheet.doc balancing.pdf balancing answers.pdf http://web.jjay.cuny.edu/~acarpi/NSC/6-react.htm GIZMO http://antoine.frostburg.edu/chem/senese/101/kits/kit_chemical_equation.html SNOWMAN BALANCING ACTIVITY: PG. 1 CHAPTER 4 REVIEW CHAPTER 4 QUIZ PG. 2 Page 190 #5, 6, 8, 11,14,15-20 PG. 3 SNC2D1 REACTION TYPES Can you see the pattern? Hopefully you realize the importance of knowing the many patterns that exist in the periodic table. Patterns help reduce the amount of things we need to memorize and also allow us to acquire information quickly. For example, knowing that an element is in group 2 tells us a lot about that element. We know it has two valence electrons, it’s a fairly reactive metal and it forms an ion with a +2 charge. There are millions of different chemical reactions that occur in the Universe. It would be quite a task to memorize the details of all of them separately. To reduce the amount that we have to know, scientists classify reactions into types. Every reaction within a type follows a particular pattern. So, instead of memorizing specific individual reactions we memorize the types of reactions and the patterns they follow. In this activity you will work in groups to try to identify things in common between different reactions of the same type. Type 1 – Synthesis Reactions 2Mg + O2 2MgO What is common about these reactions? 2Na + Cl2 2NaCl MgO + CO2 MgCO3 2H2 + O2 2H2O Type 2 – Decomposition Reactions 2KClO3 2KCl + 3O2 2Al2O3 4Al + 3 O2 H2CO3 H2O + CO2 NO3 NO + O2 What is common about these reactions? SNC2D1 Type 3 – Single Displacement Reactions Mg + Zn(NO3)2 Mg(NO3)2 + Zn What is common about these reactions? Cu + 2AgNO3 Cu(NO3)2 + 2Ag 2Na + K + CuCl2 LiI 2NaCl KI + + Cu Li Type 4 – Double Displacement Reactions Zn(NO3)2 + CuCl2 AgNO3 + ZnCl2 + Cu(NO3)2 What is common about these reactions? NaCl AgCl + NaNO3 Pb(NO3)2 + KI PbI2 + KNO3 BaCl2 + Na2SO4 BaSO4 + NaCl Classify these reactions; 2NaBr + Ca(OH)2 CaBr2 + 2NaOH 2NH3 + H2SO4 (NH4)2SO4 Pb + H3PO4 H2 + Pb3(PO4)2 Type of reaction: _______________________ Type of reaction: _______________________ Type of reaction: _______________________ Li3N + 3NH4NO3 3LiNO3 + (NH4)3N Type of reaction: _______________________ 2H2O2 2H2O + O2 Type of reaction: _______________________ Page 229 # 4, 6, 7, 9, 10 Page 240 # 4 abdef, 7abd, 8, 9, 10 SNC2D1 A C + B A + C B A + BC AC + B AB + CD AD + CB A C + B A + C B A + BC AC + B AB + CD AD + CB A C + B A + C B A + BC AC + B AB + CD AD + CB SNC2D1 HYDROCARBON COMBUSTION Read page 232 in the textbook and then answer the following questions. 1. What is common about all combustion reactions? _________________________________________________________________ _________________________________________________________________ 2. What is a hydrocarbon? _________________________________________________________________ 3. What is the general equation for the combustion of a hydrocarbon? _________________________________________________________________ 4. What importance does hydrocarbon combustion have in our lives? _________________________________________________________________ _________________________________________________________________ 5. What environmental issue is related to hydrocarbon combustion? _________________________________________________________________ 6. Sometimes the combustion of a hydrocarbon is “incomplete”. When this happens carbon monoxide is produced. What problem is associated with this? _________________________________________________________________ _________________________________________________________________ 7. Write the balanced chemical equation for the combustion of; a) methane (CH4) _________________________________________________________________ b) propane (C3H8) _________________________________________________________________ c) candle wax (C25H52) _________________________________________________________________ SNC2D1 Chemical Reactions Practice Quiz Balance and classify the following equations as either i) synthesis (S) ii) decomposition (D) iii) single displacement (SD) iv) double displacement (DD) TYPE v) combustion (C) O2 → 1. __ Cu + CuO 2. __H2O → _____H2 + _____O2 _______ 3. _____Fe + _____H2O → _____H2 + _____Fe2O3 _______ 4. _____AsCl3 + _____H2S → _____As2S3 + _____HCl _______ 5. _____CaCO3 → _____CaO + _____CO2 _______ 6. _____Fe + _____S8 → _____FeS _______ 7. _____H2S + _____KOH → _____HOH + _____K2S _______ 8. _____NaCl → _____Na + _____Cl2 _______ 9. _____Al + _____H2SO4 → _____H2 + _____Al2(SO4)3 _______ 10. _____H3PO4 + _____NH4OH → _____HOH + _____(NH4)3PO4 _______ 11. _____C3H8 + _____O2 → _____CO2 + _____H2O _______ 12. _____Al + _____O2 → _____Al2O3 _______ 13. _____CH4 + _____O2 → _____CO2 + _____H2O _______ 14. _____Al(NO3)3 + _____LiOH → _____LiNO3 + _____Al(OH)3 _______ 15. _____NaOH + _____HCl → _____NaCl + _____H2O _______ 16. _____CuCO3 → _____CuO + _____CO2 _______ 17. _____K + _____O2 → _____K2O _______ 18. _____Cl2 + _____KI → _____KCl + _____I2 _______ 19. _____KNO3 → _____KNO2 + _____O2 _______ 20. _____Zn + _____O2 → _____ZnO SNC2D1 PREDICT THE PRODUCTS 1. C10H16 + O2 ______________________________ Type of Reaction: combustion 2. MgO ______________________________ Type of Reaction: decomposition 3. Ca + CuCl2 ______________________________ Type of Reaction: single displacement 4. Al(OH)3 + H2SO4 ______________________________ Type of Reaction: double displacement 5. Rb + Br2 ______________________________ Type of Reaction: synthesis 6. Na + H2O ______________________________ Type of Reaction: single displacement 7. Ca + O2 ______________________________ Type of Reaction: synthesis 8. Zn + NaOH ______________________________ Type of Reaction: single displacement 9. Hg(OH)2 + H3PO4 ______________________________ Type of Reaction: double displacement 10. C2H6 + O2 ______________________________ Type of Reaction: combustion 11. Al + FeO ______________________________ Type of Reaction: __________________ 12. Mg + N2 ______________________________ Type of Reaction: __________________ 13. Fe2(SO4)3 + KOH ______________________________ Type of Reaction: __________________ 14. Ca3(PO4)2 + Si(CO3)2 ____________________________ Type of Reaction: __________________ 15. H2O2 ______________________________ Type of Reaction: __________________ ______________________________________________________________________ LAB #2: SINGLE DISPLACEMENT SNC2D1 ACIDS AND BASES: THE pH SCALE ACID/BASE POWERPOINT _________________ solutions are created when acids are dissolved in water to create aqueous _________________. The “acidity” of the solution is a measure of how many H+ ions are present per ________________. This largely determines how __________________ the solution is. Solutions that are very acidic are very dangerous. Strong acids are those that are needed in a relatively ____________quantity to generate __________________ solutions. _______________________ is considered to be a strong acid. ______________________ is a weak acid. It takes a __________________amount of hydrochloric acid to make a highly acidic solution. It takes a _________________ amount of carbonic acid to make a highly acidic solution. Basic solutions are created when a base is dissolved in water creating aqueous OHions. The ___________________ of the solution depends on how much base is dissolved and on the strength of the base. Neutral solutions are those that contain neither a dissolved acid or a base. To communicate how acidic or basic a solution is scientists use the pH scale. See figure 5.5 on page 196. The pH scale details; • • • • • • • ___________________________________________________ 7 represents the pH of a solution that is neither ___________________. The solution is said to be __________________. Any solution with a pH below 7 is _______________. Any solution with a pH above 7 is _____________. The more acidic or basic a solution is, the ________________________. A difference of 1 on the pH scale represents a factor of _____ in terms of acidity or basicity. A difference of 2 on the pH scale represents a factor of ______ in terms of acidity or basicity. Using figure 5.5, answer the following, 1. 2. 3. 4. 5. What is the strongest acidic solution shown? ___________________________ What is the strongest basic solution shown? _______________________ What do most of the acidic solutions have in common? _____________________ What do most of the basic solutions have in common? _____________________ How much more/less acidic/basic is/are a) Stomach acid than lemon juice? b) Milk than acid rain? c) lemon juice than milk? __________________________ __________________________ __________________________ SNC2D1 d) sea water than toothpaste? __________________________ ACID-BASE INDICATORS Acid-base indicators are substances whose colour is pH dependent. For example, a substance called litmus which is derived from plant material can be obtained in two different colours, blue and red. Blue litmus turns red in acidic solutions and red litmus turns blue in basic solutions. pH paper is a material whose colour not only indicates whether a solution is acidic or basic but also allows one to estimate pH by matching it’s colour to a chart. There are many substances that are indicators. Investigate those provided and record their colour in acidic, basic and neutral environments. Indicator Neutral Colour Colour in Acidic Solution Colour in Basic Solution Page 197 #1-4 Recognizing Acids and Bases Above, we saw how indicators can be used to test whether a solution is acidic or basic. Acids and bases can also be recognized by their unique properties. Using the textbook, perform the cut and paste activity which will help you learn the properties that are characteristic of acids and bases. Acids and bases can also be identified by their chemical formulas. The chemical formula of an acid often begins with at least one “H”. e.g. HCl HNO3 H2SO4 However, not all compounds that begin with H are acids (e.g. water). Another type of acid contains a carboxyl group. The formula for this acid type ends in COOH. Acetic acid in vinegar is this type and has the formula CH3COOH. Most common bases contain the hydroxide ion, OH-. SNC2D1 e.g. NaOH, Ca(OH)2 NOMENCLATURE Bases – these are easy. Just name them as normal “metal hydroxide” compounds. Acids – two types i) Binary – no polyatomic ion procedure: use prefix “hydro”, suffix “ic” and “acid” e.g. HCl – hydrochloric acid ii) Oxyacid – polyatomic ion procedure: no prefix, suffix “ic” and “acid” e.g. HClO3 – chloric acid (just change the “ate” to “ic”) Page 200 #1,2; page 201 #1,2; page 203 #3,4,7-9, 11 ACID – BASE NEUTRALIZATION When separate acidic and basic solutions are mixed, the H+ from the acidic solution combines with the OH- from the basic solution to form ___________. The H+ and OHare said to neutralize each other. The pH of the mixture would become closer to _____. Most neutralization reactions follow a double displacement pattern. Can you predict the products of the following acid-base reaction? HF(aq) + KOH (aq)→ General equation: _____________________________________________ The salt is made of the ____________ from the base and the ________of the acid. An application of this is in the use of antacids which people consume when they experience “heartburn”. Heartburn is caused by the production of too much stomach acid resulting in a pH that is too ______ for comfort. Consuming an antacid tablet which contains a base neutralizes some of the acid and thus ___________ the pH. Page 206 # 1-3 SNC2D1 If time; ..\..\Young 10D\Chemistry\2DCHEM_-_WS_9_(Acids_&_Bases).pdf Note: use pages 196-200 and don’t worry about task #3 – refers to a different textbook. ACID PRECIPITATION REFERENCE: PAGE 208 - 210 1. At what pH is rain classified as “acid rain”? 2. What two atmospheric gases react to form acidic rain? 3. List the human and industrial activities that contribute to the production of acid rain. 4. What problems are created by acid rain? 5. Write the word equations for the two reactions that result in the production of atmospheric H2SO4. Classify these reactions. 6. Why can some lakes resist pH changes when acid rain falls? 7. What can be added to lakes to revive them from damage caused by acid rain? Why is this not an ideal, long term solution? 8. Write the balanced neutralization equation that describes the reaction between sulphuric acid and calcium hydroxide. 9. Briefly describe two technologies that help reduce the amount of acid precipitation. _______________________________________________________________________ LAB #3 – ACID/BASE NEUTRALIZAITON SNC2D1 CHEMISTRY UNIT REVIEW What is the difference between a chemical property and a physical property? Give examples. How are elements and compounds similar? How are they different? Describe the structure of an atom in words and with a picture. What rules govern the arrangement of electrons in an atom? What name is given to the electrons in the outermost energy level? What information does the periodic table provide? Brainstorm the patterns and relationships in the periodic table. Draw a Bohr – Rutherford diagram for calcium and sulfur. Draw a Lewis symbol for carbon and selenium. What is a monatomic ion? How is a monatomic ion formed? What rules are involved? What is a multivalent metal? Give an example. What is a polyatomic ion? Give an example. What are the rules for naming ions? What is the symbol or name of the following; a) b) c) d) e) f) magnesium ion? _________ phosphide ion? _________ phosphate ion? _________ copper (II) ion? _________ nitrite ion? __________ Fe+3? __________ What are the differences between ionic and molecular compounds in terms of a) Their structure? b) Nomenclature? c) Properties? What do you look for in an formula or name when determining whether a compound is ionic or covalent? What is a diatomic molecule? Provide an example. What determines thesubscripts in the formula of an ionic compound? Give an example. Name or provide the formula for the following; 28 SNC2D1 a) b) c) d) e) f) CaI2 Barium sulfide Silver sulfate Fe2(CO3)3 Carbon dioxide NO How are Lewis symbols used to determine the structure of a molecule? Draw the structure for water and carbon dioxide. What are the indicators of chemical change? What is the Law of Conservation of Mass? In terms of a chemical reaction, what are the implications? Who are the reactants/products in a chemical reaction? Provide an example of a chemical reaction by writing the word and skeletal equations. When balancing a chemical equation, what are you allowed to change? Write and balance the equation that describes the combustion of propane (C3H8). What are the 6 types of reactions studied in this course? Provide the general “pattern” equation and an example for each type. What issues are associated with the combustion of a hydrocarbon? How do you identify an acid/base from it’s formula? What are the naming rules for binary acids and oxyacids? Provide examples for each. What are the details of the pH scale? 29