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Vocabulary Chemistry M.4 Lesson 1 Atom and Periodic Table by Angka Teprattananan 1 angka teprattananan conclude conductivity matter divide agree made up theory compose destroy combine definite voltage pressure electric current electric field negative charge to mass appear discover positive angka teprattananan Greek Model Over 2,000 years ago Democritus concluded that matter could not be divided into smaller and smaller pieces forever Named the smallest piece atomos Democritus ¨o˹ ´oŵa¹ ( John Dalton ) (c460-371 BC) Aristotle (384-322 BC) But Aristotle didnt agree with the concept of atoms. Aristotle thought the earth was composed of matter - which made up of four elements: earth, air, fire, and water. angka teprattananan 3 angka teprattananan 2 Daltons Atomic model 1. All elements are composed of atoms. It is impossible to divide or destroy an atom. 2. All atoms of the same elements are alike. 3. Atoms of different elements are different. 4. Different atoms combine to form a compound in definite whole number ratios. e.g. H2O , CO2 (Expect Na ,H2 , Br2 , P4 , S8) 4 (Daltons atomic model) J.J. Thomson e¨ e¨ ·oÁÊa¹ (J.J. Thomson) oaµoÁÁÕû٠ÃÒ§e»¹·Ã§¡ÅÁ ÁÕ¢¹Ò´eÅç¡ äÁÊÒÁÒö溧æ¡æÅaÊÙËÒÂä´ angka teprattananan Passing an electric current makes a beam appear to move from the cathode to the anode end. 5 angka teprattananan ‐ OFF – Discovered by Eugen Goldstein – He observed Canal rays and found that they are composed of positive particles Proton. voltage source + 6 Discovery of the Proton Thomsons Experiment ON Studied electrical conductivity of gases by using a cathode ray tube in high voltage and low pressure. + Eugen Goldstein ‐ By adding an electric field , he found that the moving pieces were negative. And negative particle was called Electron Thomson was able to measure the charge to mass ratio of the electron q/me = 1.76 x 108 coulombs/gram angka teprattananan 7 angka teprattananan 8 Canal Rays ¨Ò¡¡Ò÷´Åo§¢o§o¡Å´Êäµ¹ ÊÃu»ä´ÇÒ - Ãa§ÊպǡËÃืoo¹uÀÒ¤ºÇ¡e¡i´¨Ò¡æ¡Ê·ÕèºÃèuÀÒÂã¹ËÅo´Ãa§ÊÕ æ¤o·´ «ึè§eºÕÂè §eº¹e¢ÒËÒ¢aéÇź䴷aé§ã¹Ê¹ÒÁä¿¿ÒæÅaʹÒÁæÁeËÅç¡ - Ãa§ÊպǡÁÕ¤Ò oaµÃÒÊǹ»Ãa¨uµoÁÇÅäÁ¤§·Õè ¢ึé¹oÂÙ¡aºª¹i´¢o§ æ¡Ê·ÕèºÃèuoÂÙÀÒÂã¹ËÅo´Ãa§ÊÕæ¤o·´ - ¶Òe»ÅÕÂè ¹æ¡Êe»¹äÎo´Ãe¨¹ ¨a¾ºÇÒo¹uÀÒ¤ºÇ¡·Õèe¡i´¢ึ鹨aÁÕ ¤Ò»Ãa¨ue·Ò¡aºoieÅ硵Ão¹¾o´Õ ¨ึ§eÃÕ¡o¹uÀÒ¤ºÇ¡¹ÕéÇÒ o»Ãµo¹ Canal Rays passed through holes, or channels, in the reverse direction as the cathode ray. _ cathode _ anode + 9 angka teprattananan Mass of the Electron angka teprattananan 10 Calculate mass of the Electron 1. charge to mass ratio = 1.76x108 coulombs/gram 2. charge of electron: = 1.60 x 10-19 g The oil drop apparatus Millikan determines the charge of the electron : 1.60 x 10-19 C and the mass of the electron: 9.1 x 10-28 g angka teprattananan 11 angka teprattananan 12 Thomsons Atomic Model Vocabulary (Plum Pudding Model) oaµoÁe»¹·Ã§¡ÅÁ »Ãa¡oº´ÇÂo»Ãµo¹·ÕèÁÕ»Ãa¨uºÇ¡æÅaoieÅ硵Ão¹ ·ÕèÁÕ»Ãa¨uźoÂÙoÂÒ§¡Ãa¨a´¡Ãa¨Ò æÅaÊíÒËÃaºoaµoÁ·Õèe»¹¡ÅÒ§·Ò§ ä¿¿Ò¨aÁÕ¨íҹǹo»Ãµo¹e·Ò¡aº¨íҹǹoieÅ硵Ão¹¾o´Õ 13 angka teprattananan Discovery of Nucleus Ernest Rutherford angka teprattananan Tested Thomsons model of atomic structure with the gold foil experiment. Bombarded thin gold foil with a beam of alpha particles. If the positive charge was evenly spread out, the beam should have easily. passed through. 15 bombarded emit experiment symbol gold foil spread out passed through refract reflect empty space distribute occupy atomic number mass number subatomic particle equal angka teprattananan 14 Most of the particles passed through A few particles were refracted VERY FEW were greatly reflected angka teprattananan 16 Based on his experimental evidence: The atom is mostly empty space All the positive charge, and almost all the mass is in a small area in the center. He called this a nucleus The electrons distributed around the nucleus, and occupy most of the volume His model was called a nuclear model angka teprattananan 17 Rutherford's Atomic Model oaµoÁ»Ãa¡oº´Ç¹iÇe¤ÅÕÂÊ«ึè§ÁÕ»Ãa¨uºÇ¡(o»Ãµo¹)oÂٵç¡ÅÒ§ ÁÕ¢¹Ò´eÅç¡ÁÒ¡æÅaÁÕÁÇÅÁÒ¡ ÊǹoieÅ硵Ão¹·ÕèÁÕ»Ãa¨uźæÅaÁÕÁÇŹo e¤Åืoè ¹·ÕèÃoº¹iÇe¤ÅÕÂÊe»¹ºÃiedz¡ÇÒ§" angka teprattananan The Discovery of the Neutron Chadwick bombarded alpha particles at Beryllium. Neutrons were emitted and in turn hit parafin and ejected protons from the parafin. Neutrons have mass similar to protons. No electrical charge. 18 The Subatomic particles Subparticle James Chadwick electron proton neutron symbol e p n charge -1 +1 0 mass(g) 9.1x10-27 1.67x10-24 1.67x10-24 mass(amu) 0.0005 1.0072 1.0086 THE MASS OF THE NEUTRON IS 1839 times greater than an electron. Composition of the Nucleus: • nuclei are composed of "nucleons": protons and neutrons • atomic mass units: 1 amu = exactly 1/12 the mass of a carbon12 nucleus angka teprattananan 19 angka teprattananan 20 ¤ÇÒá ¤ืo o¹uÀÒ¤·ÕèeÅç¡·ÕèÊ´u e·Ò·ÕèÁÕ¡ÒÃÂoÁÃaº »¨¨uºa¹ÁÕ ¡Òä¹¾º ¤ÇÒá 6 µaÇ ¤ืo up quark, down quark, strange quark, charmed quark, bottom quark æÅa top quark - ¹iǵÃo¹ »Ãa¡oº´Ç up quark 1 µaÇ æÅa down quark 2 µaÇ - o»Ãµo¹ »Ãa¡oº´Ç up quark 2 µaÇ æÅa down quark 1 µaÇ Atomic Symbol (Nuclear Symbol) • Contain the symbol of the element, the mass number and the atomic number. Mass number A Atomic number Z Element Symbol X • Atomic number = number of protons – Same as the number of electrons in a neutral atom • Mass number = the number of protons + neutrons angka teprattananan 21 9 4Be 14 6C 35 17Cl 74 33As 3- 44 20Ca 2+ 67 3+ 31Ga Atomic Number Mass Number # of Protons # of Neutrons • Isotope are atoms of the same element having different masses, due to varying numbers of neutrons. 1 H Subatomic particles p=1 ,e=1 , n=0 1 2 H Subatomic particles p=1 ,e=1 , n=1 1 • Isotone are atoms of the different element having equal neutrons. 11 B Subatomic particles p=5 ,e=5 , n=6 5 12 C Subatomic particles p=6 ,e=6 , n=6 6 # of Electrons angka teprattananan 22 Isotope , Isotone , Isobar and Isoelectronic Fill in the blanks for the following nuclear symbols: Element angka teprattananan 23 angka teprattananan 24 For each of the following ,check the blank for isotope , isotone , isobar or isoelectronic • Isobar are atoms of the different element having equal mass number. 36 S mass no. of 3616S is 36 16 36 Ar mass no. of 36 Ar is 36 18 18 Neclear symbols 14 20 10Ne 24 Mg2+ 12 Subatomic particles Subatomic particles p = 10 , e = 10 , n = 10 p = 12 , e = 10 , n = 12 25 angka teprattananan & excited State electromagnetic wave relationship wavelength frequency energy ground State describe angka teprattananan angka teprattananan Max Plank energy levels quantize less-stable absorbing releasing 27 isotone isobar isoelectronic 7N 19K Vocabulary spectrum 14 & 4020Ca 35 Cl & 37 Cl 17 17 38 Ar & 32 S218 16 16 O & 18 O 8 8 40 Ar & 40 Ca 18 20 35 Cl- & 39 K+ 17 19 31 P & 32 S 15 16 39 • Isoelectronic are atoms of the different element having equal electron. 6C isotope 26 Max Plank studied a spectrum of Electromagnetic Wave. The relationship among the wavelength (λ), the frequency (ν), and the energy (E) are: or where c is Speed of light = 3 x 108 m/s h is Planck's Constant = 6.626 x 10-34 J.s is Frequency (Hz) λ is wavelength (m) angka teprattananan 28 Energy and frequency of Electromagnetic Wave Color of spectrum Violet Blue Green Yellow Orange Red Wavelength (nm) 400 420 490 580 590 650 - 420 490 580 590 650 700 Energy (kJ) 4.96x10-22 4.73x10-22 4.05x10-22 3.42x10-22 3.36x10-22 3.05x10-22 - 4.73x10-22 4.05x10-22 3.42x10-22 3.36x10-22 3.05x10-22 2.83x10-22 Calculate about Electromagnetic Wave Ex1 Êe»¡µÃaÁÊÕÁǧ¤ÇÒÁÂÒǤÅืè¹ 500 nm ¨aÁÕ¤ÇÒÁ¶Õèe·Òã´ frequency(Hz) 7.49x1014 - 7.14x1014 7.14x1014 - 6.12x1014 6.12x1014 - 5.17x1014 5.17x1014 - 5.08x1014 5.05x1014 - 4.16x1014 4.61x1014 - 4.28x1014 Ex2 Êe»¡µÃaÁÊÕæ´§ÁÕ¤ÇÒÁÂÒǤÅืè¹ 500 nm ¨aÁÕ¤ÇÒÁ¶ÕèæÅa¾Åa§§Ò¹e·Òã´ Êe»¡µÃaÁ ¤ืo 涺ÊÕ·Õèe¡i´¨Ò¡¡ÒÃe»ÅÕè¹æ»Å§¾Åa§§Ò¹¢o§¤Åื¹è æÁeËÅç¡ä¿¿Ò angka teprattananan 29 angka teprattananan 30 Niels Bohr studied a spectrum of Hydrogen atom. discovered the four lines of Hydrogen spectrums Violet , Blue , Blue-green ,and Red. Ex3 The energy of electromagnetic wave is 3x10-22 KJ , Find the color Niels Bohr Ex4 The frequency is 5x1014 Hz , calculate the wavelength , energy and find the color of this spectrum. How did the spectrum appear ? angka teprattananan 31 angka teprattananan 32 Bohr used the term energy levels (or shells) to describe. He said that the energy of an electron is quantized, meaning electrons can have one energy level or another but nothing in between. The energy level an electron normally occupies is called ground state. But it can move to a higherenergy (less-stable) by absorbing energy. This higher-energy is called excited state. angka teprattananan After its done being excited, the electron can return to its original ground state by releasing the energy it has absorbed, as shown in the diagram below. 33 angka teprattananan 34 35 angka teprattananan 36 • Table show the energy of Hydrogen spectrum Color of Spectrum Wavelength (nm) Energy (kJ) Red 656 3.02 x 10-22 Δ E 10.6 x 10-23 Bluegreen 486 4.08 x 10-22 4.9 x 10-23 Blue 434 4.57 x 10-22 2.7 x 10-23 Violet angka teprattananan 410 4.84 x 10-22 Bohrs Atomic Model Electron Configuration (o¤Ã§æººoieÅ硵Ão¹) Electrons orbit the nucleus in definite principle energy levels (7 principle energy levels). The principle energy level can hold only a specific number of electrons. Rule ; 2n2 n= oaµoÁ»Ãa¡oº´ÇÂo»Ãµo¹æÅa¹iǵÃo¹ oÂÙÀÒÂã¹¹iÇe¤ÅÕÂÊ ÊǹoieÅ硵Ão¹Çi§è oÂÙÃoº æ ¹iÇe¤ÅÕÂÊe»¹ªa¹é æ ËÃืoe»¹Ãa´aº¾Åa§§Ò¹«ึè§ ÁÕ¤ÒäÁµoe¹ืèo§¡a¹ angka teprattananan 37 Principle energy levels n n n n n n n = = = = = = = 1 2 3 4 5 6 7 angka teprattananan 38 Rule; Arrangements of electrons in an atom. Maximum Electrons 1. Lowest levels are filled first. 2. Once a level is full, the electrons start filling the next level. 3. Outer level (valence electrons) has maximum electrons equal 8 and next outer level has maximum 8 or 18 electrons. e.g. 11Na: has 11 electrons 2e 8e 18 e 32 e 50 e 72 e 98 e First energy level 1 (n =1) can fill 2 electrons Second energy level 2 (n =2) can fill 8 electrons Third energy level 3 (n =3) 1 electron Or shot hand angka teprattananan principle energy levels 39 angka teprattananan 11Na can fill : 2,8,1 40 Arrangements of electrons in an atom. 1. 3Li : 2. 12Mg : 3. 19K : 4. 33As : 5. 53I : 6. 55Cs : 7. 82Pb : 8. 88Ra : 9. 22Ti : 10. 28Ni : Vocabulary angka teprattananan explain surround electron cloud closest outermost impossible exact location predict 41 42 angka teprattananan Electron Cloud Model Modern Atomic model Electrons with the lowest energy are found in the energy level closest to the nucleus. Electrons with the highest energy are found in the outermost energy levels, farther from the nucleus. It is impossible to determine the exact location of an electron only predict where is could be based on how much energy it has. Bohrs model could not explain complex atoms(can explain Hydrogen atom only). Atom has a small positively charged nucleus surrounded by a region of negatively charged electrons to make the entire atom neutral. called the electron cloud. angka teprattananan sub-energy levels exclusion principle spin unpair configuration notation indicate 43 Erwin Schrodinger angka teprattananan 44 The region of electrons move around the nucleus in other shapes, called Orbital There are 4 kind of orbitals (sub-energy levels) e.g. s , p , d and f s p d f 45 angka teprattananan Arrangements of electrons in Orbital principle energy levels sub-energy levels maximum electron (shell) n = 1 (subshell) s 2 n = 2 s,p 8 n = 3 s,p,d 18 n = 4 s,p,d,f 32 n = 5 s,p,d,f 32 n = 6 s,p,d 18 n = 7 s,p 8 n = 8 s 2 angka teprattananan Electron configurations By using , 1. Pauli exclusion principle; Each orbital can have only 2 electrons and have not the same spin. 2. Aufbau principle; Electron fill lowest energy levels first. 3. Hunds Rule; For atoms in ground state, the number of unpaired electrons is the maximum possible and have the same spin. angka teprattananan 46 Lower energy Higher energy 1s 2s 2p 3s 3p 4s 3d 4p . 47 angka teprattananan 48 Ex. Give the full electron configuration of 27Co Chemists use a standard notation to indicate the electron configurations of atoms and molecules. 1) Orbital Diagram. 4d 1s 5S 4P 3d 2) Long notation or spdf configuration. 1s22s22p63s2.... 3) Shorthand Notation or noble gas core. [Ne]3s23p4 4S 3P NOTE. principle energy levels Or 27Co; 3S 2P 2S 49 1S angka teprattananan Using Orbital Diagram 1. 3Li : 2S 12Mg 3. 18Ar 4. 19K 5. 25Mn : 6. 26Fe : 7. 24Cr : : : angka teprattananan 50 Using Long Notation or spdf configuration 1. 12Mg : 1s2 2s2 2p6 3s2 2. 18Ar : 3. 19K : 4. 33As : 5. 38Sr : 6. 55Cs : 7. 28Ni : 8. 24Cr : 9. 29Cu : . 2. angka teprattananan : 1S 2s 51 angka teprattananan 52 Using Short hand 1. 3Li : 2. 12Mg : 3. 18Ar : 4. 19K : 5. 33As : 6. 28Ni : 7. 37Rb : 8. 53I : Notation or Noble Gas core. [He]2s1 angka teprattananan The History of the Periodic Table (ÇiÇa²¹Ò¡Òâo§µÒÃÒ§¸Òµu) 53 angka teprattananan Vocabulary similar property conductor middle element roughly publish organize increasing regular interval according to clear up electricity luster ductile malleable reflect except semiconductor stair step angka teprattananan Johaun Dobereiner Cl Br I 54 He noticed that chlorine, bromine and iodine had similar properties. And the atomic mass of the middle element was roughly the average of the masses of the others . He called Law of Triads Chlorine mass = 35.5 Bromine mass = 79.9 Iodine mass = 126.9 Average mass of chlorine and iodine = (35.5 + 126.9) / 2 = 81.9 (close to Br!) Dobereiners other triads included lithium (Li), sodium (Na) and potassium (K), along with calcium (Ca), strontium (Sr) and barium (Ba). 55 angka teprattananan 56 He noticed that every 8th element had similar properties, a bit like a musical scale. He listed some of the known elements in rows of 7 as shown below. He called Law of Octaves . John Newlands Dmitri Mendeleev In 1869 he published a table of the elements organized by increasing atomic mass. Noticed similar properties appeared at regular intervals --> periodic Mendeleev Lothar Meyer At the same time, he published his own table of the elements organized by increasing atomic mass. Lothar Meyer His law of octaves work today with the first 20 elements. angka teprattananan 57 58 The table below compares Mendeleevs prediction with the actual data. Mendeleev’s discovery angka teprattananan angka teprattananan 59 angka teprattananan 60 Modern Periodic Table Henry mosely The Periodic Table was then arranged according to increasing atomic number. Henry mosely The table was as it is now and cleared up the Tellurium and Iodine problem. Periodic Law : the physical and chemical properties of elements are periodic functions of their atomic number and electrons arrangement. 61 angka teprattananan Three classes of elements are Metals, Nonmetals and Metalloids angka teprattananan Metal Elements Nonmetal Elements Good conductors of heat and electricity Have luster, are ductile , malleable , good reflect light All metals are solids at room temperature ,except for mercury(Hg) Found on left side of periodic table and some on right side of table Have properties that are opposite to those of metals Not good conductors of heat and electricity, poor reflect light Usually brittle solids or gases ,except for bromine(Br) Found on right side of periodic table AND hydrogen 62 Gold Sulphur angka teprattananan 63 angka teprattananan Bromine 64 Some properties of Metalloids , Al(metal) and I(nonmetal) Metalloids IE1 Sometimes called semiconductors Form the stairstep between metals and nonmetals Have properties of both metals and nonmetals Examples: B, Si , Ge , As , Sb, Te and, At angka teprattananan (kJ/mol) 65 - B Si Ge As Sb Te Po At have high first ionization energy(IE1) , electronegativity (EN) and can form Ionic and Covalent compounds same nonmetals. - High melting point and boiling point , high density and can electrical conductivity same metals. - So this elements will called Metalloids (Po and At is radioactive element) angka teprattananan 67 Al B 584 807 Si 793 Ge As Sb I 768 951 840 1015 Type of EN Density meltingboiling Electical o (g/cm3) Conductivity Compound point( C) 1.61 2.70 660-2519 ionic √ 2.04 2.34 2075-4000 ionic and covalent √ 1.90 2.33 1414-3265 ionic and network √ covalent 2.01 5.32 938-2833 ionic and covalent √ 2.18 5.75 358-603 ionic and covalent √ 2.05 6.68 631-1587 ionic and covalent √ 2.66 4.93 114-184 X ionic and covalent 66 angka teprattananan Location of Hydrogen in the periodic table Some properties of Hydrogen , group IA and properties Group IA H 1. # valence electron 1 1 2. Oxidation number in +1 +1 , -1 compounds 3. IE1 (kJ/mol) 382-526 1318 4. EN 0.7-1.0 2.1 5. phase solid gas 6. Electric conductivity can cannot VIIA group VIIA 7 +1 , +3 , +5 +7 , -1 1015-1687 2.2 -4.0 3 phase cannot chemist will arrange Hydrogen in group IA and VIIA in the periodic table. 68 angka teprattananan Periodic Table Vocabulary vertical gain horizontal consist shiny silvery react characteristic flame soluble encounter discharge pale diatom monoatom inert gases incapable synthesis order digit The elements in same group of the periodic table have similar physical and chemical properties! The vertical columns of the periodic table are called GROUP, or FAMILY. (18 groups) 69 angka teprattananan 70 angka teprattananan Periodic Table Periodic Table The s and p block elements are called REPRESENTATIVE ELEMENTS (Group A) The d and f block elements are called TRANSITION ELEMENTS (Group B) s p d The horizontal rows of the periodic table are called PERIOD.(7 periods) angka teprattananan 71 f angka teprattananan 72 REPRESENTATIVE ELEMENTS (Group A ; 8 groups) Alkali Earth Metals Halogens Group IA (Alkali Metals) Noble Gases Inert Gases Alkali Metals 73 angka teprattananan Alkali Metals can react with oxygen to give different oxide compounds : 4Li(s) + O2(g) 2Li2O(s) Group I metals are shiny , silvery solids. All are soft and can easily cut with a knife. Have low density. react easily in air. They are kept under oil. Group I elements are called alkali metals because they react with water to give alkaline solution. e.g. 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) angka teprattananan 74 Group IIA (Alkali Earth Metals) Alkali Earth Metals have higher density than Alkali Metals carbonate , phosphate , sulphid , sulphite compounds of Alkali Earth Metal cannot soluble in water. Be does not react with water , Mg react slowly with water and Ca and the elements below it react readily with water: Mg(s) + 2H2O(l) Mg(OH)2(aq) + H2(g) Ca(s) + 2H2O(l) Ca(OH)2(aq) + H2(g) (oxide) 2Na(s) + O2(g) Na2O2(s) (peroxide) K(s) + O2(g) KO2(s) (superoxide) Alkali Metals emit a characteristic color when placed in a flame. All alkali compounds can soluble in water. Group I elements become more reactive down the group. angka teprattananan 75 angka teprattananan 76 Group VIIA (Halogens) Group VIA (Chalcogen) Oxygen , Sulphur and Selenium are nonmetals , Tellurium is Metalloid and Polonium is radioactive element. Oxygen is encountered in two molecular forms , O2 and O3. O3 is also formed from O2 in electrical discharges, such as in lightning storms: 3O2(g) 2O3(g) H = +284.6 kJ Ozone is toxic. angka teprattananan Halogen always gain one electron to form anion: X2 + 2e- 2X Fluorine is most reactive in the group: 2F2(g) + 2H2O(l) 4HF(aq) + O2(g) • Each element consists of diatom molecules ; F2 , Cl2 , Br2 and I2 Fluorine gas is pale yellow , Chlorine gas is yellowgreen , Bromine liquid is red-brown and solid iodine is black (violet vapor) 77 Group VIIIA(Noble gases) • Fluorine and Chlorine are more reactive than Bromine and Iodide • Noble gases are monoatom (He Ne Ar Kr Xe Rn) • Noble gases have completely filled s and p subshell. • 1960s the elements were called the inert gases because they were thought to be incapable of forming chemical compounds. • Today we can synthesis some of noble gas compounds ; XeF2 XeF4 XeF6 KrF2 and HArF 2Cl-(aq) + F2(g) 2F-(aq) + Cl2(g) 2Br-(aq) + Cl2(g) 2Cl-(aq) + Br2(g) 2I-(aq) + Br2(g) 2Br-(aq) + I2(g) X 2F-(aq) + Cl2(g) X 2Cl-(aq) + Br2(g) 2Br-(aq) + I2(g) X In fact, fluorine removes electrons from almost any substance with which it come into contact. angka teprattananan 78 angka teprattananan 79 angka teprattananan 80 TRANSITION ELEMENTS (Group B ; 8 groups) Electron Configuration and Properties Transition Metals InnerTransition Metals Rare-earth elements angka teprattananan 81 82 angka teprattananan Oxidation Number of Transition Metals Phisical Properties of Potassium - Zinc (Stable Oxidation Number in red) angka teprattananan 83 angka teprattananan 84 Nomenclature of Elements with Atomic Numbers Greaterer than 100 Write the element symbol and name : The Rules for Naming Elements 1. Name directly from the atomic number of the element using the following numerical roots 0 = nil , 1 = un , 2 = bi , 3 = tri , 4 = quad , 5 = pent , 6 = hex , 7 = hept , 8 = oct , 9 = enn 2. The roots are put together in the order of the digits and terminated by ium to spell out the name. Example Atomic Number : 112 Element Name: Ununbium Element Symbol: Uub 85 angka teprattananan Location of atoms in the periodic table 17Cl : : 17Cl angka teprattananan 3. Atomic Number : 115 4. Atomic Number : 118 5. Atomic Number : 120 Name : Symbol Name : Symbol Name : Symbol Name : Symbol Name : Symbol ___________ : ___________ ___________ : ___________ ___________ : ___________ ___________ : ___________ ___________ : ___________ 86 angka teprattananan e.g. Outer level 21Sc 1s2 2s2 2p6 3s2 3p5 valence electron 2,8,7 : 1s2 2s2 2p6 3s2 3p6 4s2 3d1 /2+1 = 3 4 principle energy levels So, Sc is in group 3B and period 4. Three shells So, 2. Atomic Number : 110 Element Element Element Element Element Element Element Element Element Element For Transiton metals (group B) group no. = sum of two last sub-energy levels (subshell) period no. = no. of principle energy levels For representative elements (group A) group no. = no. of valence electron = sum of electron outer level period no. = no. of principle energy levels Ex. 1. Atomic Number : 102 is in group 7A and period 3 87 angka teprattananan 88 Vocabulary Fill in the blank , Determine Group No. and Period No. 1. 7N : group period 2. 11Na : group period 3. 18Ar : group period 4. 20Ca : group period 5. 35Br : group period 6. 25Mn : group period 7. 26Fe : group period 8. 22Ti : group period 9. 53I : group period 10. 29Cu : group period angka teprattananan 89 Radioactive turned into unstable falls down radiation equation Ionising ability Balancing Penetrating half life behavior undergo electric field decrease excessive collide repulsion Fission Decay Fussion 90 angka teprattananan Properties of radiation Radioactive Elements A radioactive elements are an elements with an unstable nucleus, which radiates alpha, beta or gamma radiation and gets converted to a stable element. 3 Types of Radiation Type of Radiation Alpha particle Beta particle Gamma ray Symbol (can look different, depends on the font) Mass (atomic mass units) 4 1/2000 0 Charge +2 -1 0 Speed slow fast very fast (speed of light) Ionising ability high medium 0 Penetrating power low medium high paper aluminium lead Stopped by: Penetrating power angka teprattananan 91 angka teprattananan 92 The behavior of three types of radioactive emissions in an electric field. angka teprattananan 93 Beta Decay Alpha Decay The reason alpha decay occurs is because the nucleus has too many protons which cause excessive repulsion. 94 angka teprattananan Gamma Decay Beta decay occurs when the neutron to proton ratio is too great in the nucleus and causes instability. In basic beta decay, a neutron is turned into a proton and an electron. The electron is then emitted. Gamma decay occurs because the nucleus is at too high an energy. The nucleus falls down to a lower energy state and, in the process, emits a high energy photon known as a gamma particle. 3 angka teprattananan 95 angka teprattananan 2He* 3 2He + γ 96 Symbol charge and mass Nuclear equation Partical Symbol Charge mass(amu)* Alpha α , 42He +2 4.00276 Beta β, -1 0.000540 0 0 +1 0.000540 0 -1e γ Gamma Positron β+ , Neutron n , 1 0n 0 1.0087 Proton P , 1H 1 +1 1.0073 Deuteron D , 2H 1 +1 2.0136 Tritron T , 3H 1 +1 3.0219 angka teprattananan 0 +1e Balancing Nuclear Equations Ex. 1: 1 66 29Cu C. 27 13Al _______ 97 + 42He D. 146C E. 226 F. 226 angka teprattananan 30 13 6C 14Si 98 angka teprattananan G. 213 -1e H. 209 + _______ I. 23 J. 238 + 0 + ________ 83Bi _______ + 42He 81Tl 209 11Na + 42He 92U + 16 90 + L. 23592U + 1 99 angka teprattananan + _______ 0n 87Fr __________ 12Mg 239 16 222 26 8O K. 23892U + 89Ac + _______ ________ +510n + ________ 226 82Pb 8O 88Ra 89Ac 9 6 4 1H + 4Be ---> 3Li + 2He Rule: The sum of the mass numbers of the reactants equals the sum of the mass numbers of the products. Balancing Nuclear Equations _______ + 0-1e A. 2714Si B. A nuclear equation shows how a nucleus gains or loses subatomic particles. 94Pu + ________ 38Sr + 143 54Xe + ________ 100 Radioactive Elements Half life ; t½ is the period of time it takes for the amount of a substance undergoing decay to decrease by half. Ex. P-32 has a half life 14 days 100 g 14 วัน 14 วัน 50 g 25 g angka teprattananan 101 µaÇoÂÒ§ ¶Ò·ié§äoo«o·»¡aÁÁa¹µÃa§ÊÕª¹i´Ë¹ึè§ 20 ¡ÃaÁ äǹҹ 28 Ça¹ »ÃÒ¡¯ ÇÒÁÕäoo«o·»¹aé¹eËÅืooÂÙ 1.25 ¡ÃaÁ ¤Ãึ觪Õǵi ¢o§äoo«o·»¹ÕéÁÕ¤Òe·Òã´ Half life Radiation U-235 7.1x109 years Alpha Gamma C-14 5,760 years Beta Co-60 5.26 years Gamma Au-198 2.7 days Beta Gamma I-125 60 days Gamma I-131 8.07 days Beta Gamma P-32 14.3 days Beta Pu-239 24,000 years Alpha Gamma K-40 1x109 years Beta Ra-226 1,600 years Alpha Gamma angka teprattananan Benefit Treatment of Cancers Archeology Treatment of Cancers Medical Diagnostics Medical Diagnostics Medical Diagnostics Treatment of Cancers Generation of Electricity Archeology Treatment of Cancers 102 1. After 42 days a 2.0 g sample of phosphorus-32 contains only 0.25 g of the isotope. What is the half-life of phosphorus-32? 2. In 5.49 seconds, 1.20 g of argon-35 decay to leave only 0.15 g. What is the half-life of argon-35? µaÇoÂÒ§ ¨§ËÒ»ÃiÁÒ³ I-131 eÃièÁµ¹ eÁืèo¹íÒ I-131 ¨íҹǹ˹ึè§ÁÒÇÒ§äÇ e»¹eÇÅÒ 40.5 Ça¹ »ÃÒ¡¯ÇÒ ÁÕÁÇÅeËÅืo 0.125 ¡ÃaÁ ¤Ãึ§è ªÕÇiµ¢o§ I-131 e·Ò¡aº 8.1 Ça¹ angka teprattananan Elements 103 angka teprattananan 104 Calculations base on half life 5. Polonium-214 has a half-life of 164 seconds. How many seconds would it take for 8.0 g of this isotope to decay to 0.25 g? Nt = N0 2n n = T / t1/2 = = = = = number remaining initial number time no. time of decay half life µaÇoÂÒ§ ¨§ËÒ»ÃiÁÒ³¢o§ Tc-99 ·ÕèeËÅืoeÁืèoÇÒ§ Tc-99 ¨íҹǹ 18 ¡ÃaÁäǹҹ 24 ªaèÇoÁ§ æÅa Tc-99 ÁÕ¤Ãึ觪ÕÇiµ 6 ªaèÇoÁ§ 6. How many days does it take for 16 g of palladium-103 to decay to 1.0 g? The half-life of palladium-103 is 17 days. angka teprattananan Nt N0 T n t1/2 105 106 angka teprattananan Nuclear Reaction 1. After 42 days a 2.0 g sample of phosphorus-32 contains only 0.25 g of the isotope. What is the half-life of phosphorus-32? Nuclear Reaction is process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, or high energy electron) from outside the atom, collide to produce products different from the initial particles. 2. Polonium-214 has a half-life of 164 seconds. How many seconds would it take for 8.0 g of this isotope to decay to 0.25 g? 2 Types of nuclear reaction 1. Nuclear Fission 2. Nuclear Fussion angka teprattananan 107 angka teprattananan 108 Nuclear Fission A heavy nucleus such as Uranium-235 absorbs an extra neutron, it becomes unstable and splits into two lighter nuclei. The energy is released as kinetic energy of the fission products. 109 angka teprattananan Nuclear Fussion When two light nuclei such as Hydrogen or Deuterium are forced to combine forming a new, heavier nucleus. The energy is released as kinetic energy of the fusion products. angka teprattananan 110 Atomic Properties and Periodic Trends Atomic Properties Atomic radius (¢¹Ò´oaµoÁ) Ion size (ÃaÈÁÕäooo¹) Ionization energy (IE) (¾Åa§§Ò¹äoooä¹e«ªa¹) Electron affinity (EA) (ÊaÁ¾ÃäÀÒ¾oieÅ硵Ão¹) Electronegativity (EN) (oieÅç¡o·Ãe¹¡ÒµiÇiµÕ) Melting point(m.p.) (¨u´ËÅoÁeËÅÇ) and Boiling point(b.p.) (¨u´e´ืo´) Oxidation Number(O.N.) (eÅ¢oo¡«ie´ªa¹) and Periodic Trends (ÊÁºaµi¢o§¸ÒµuæÅaæ¹Ço¹Á¢o§¸ÒµuµÒÁµÒÃÒ§¸Òµu) angka teprattananan 111 angka teprattananan 112 Atomic Radius (Atomic Size) Vocabulary distance discontinuity repulsion endothermic attraction exothermic trend tendency Cation combine anion require Network structure indicate inversely giant molecules The atomic radius is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined. proportional angka teprattananan 113 A Kind of Radius 1. Covalent Radius(ÃaÈÁÕo¤eÇeŹµ) used for Covalent compounds. e.g. H2 , F2 , Cl2 , O2 Atomic Radius Group trends : The atoms get bigger as we go down a group. Because the increase in the principal energy levels. Cl - Cl 2. Van der Waals Radius(ÃaÈÁÕæǹe´oÃÇÒÅÊ) used for Noble gases. e.g. He , Ne , Ar Period Trends : The atoms get bigger as we go from right to left in a period at same energy level. Because the decrease of nucleus attraction. 3. Metallic Radius(ÃaÈÁÕoÅËa) used for Metal atoms. e.g. Li , Mg , Cu angka teprattananan 114 angka teprattananan 115 angka teprattananan 116 Atomic Radius 1. Which element in each pair has the larger atoms? 1.2 3Li or 8O 1.1 12Mg or 20Ca 1.3 17Cl or 35Br 1.4 11Na or 16S 2. Arrange these atoms in order of increasing size? 11Na , 13Al , 6C , 20Ca 3. Arrange these atoms in order of increasing size? 33As , 37Rb , 18Ar , 15P 117 angka teprattananan 6.3 The Octet Rule 118 angka teprattananan Ions size Metals elements lose valence electrons to form cation. Cation radius are always smaller than atomic radius. The goal of most atoms is to have an octet or group of 8 electrons in their valence energy level. Metals generally give(lose) electrons, Nonmetals take(gain) electrons from other atoms. Non-metal elements gain valence electrons to form anion. Anion radius are always larger than atomic radius. Atoms that have gained or lose electrons are called ion. angka teprattananan 119 angka teprattananan 120 Group trends The ions get bigger as we go down a group. Because the increase in the principal energy levels. Period Trends The ions get bigger as we go from right to left in a period at same energy level. Because the decrease of nucleus attraction. Atoms and Ions size B3+ Li+ Be2+ C4+ N3- O2- F121 angka teprattananan 4. + 11Na or 12Mg2+ 2. Arrange these atoms and ions in order of increasing size? 2+ , 3+ , 3- , 12Mg 13Al 15P 17Cl 3. Arrange these atoms and ions in order of increasing size? + + 23Li , 11Na , 12Mg , 16S angka teprattananan 122 Ionization Energy(IE) 1. Which atoms or ions in each pair are larger? 2. 8O or 8O21. 12Mg or 12Mg2+ 3. 7N3- or 9F- angka teprattananan 123 The energy required to remove an electron from an atom in gas phase. Ionization energy and atomic radius are inversely proportional. e.g. First Ionization Energy(IE1) Na(g) --> Na+(g) + e Second Ionization Energy(IE2) Na+(g) --> Na2+(g) + e angka teprattananan 124 Find the group number from ionization of following element ? Write IE1 IE5 of Boron ______ ______ ______ ______ ______ __________________ __________________ __________________ __________________ __________________ : : : : : IE1 = 807 KJ/mol IE2 = 2,433 KJ/mol IE3 = 3,666 KJ/mol IE4 = 25,033 KJ/mol IE5 = 32,834 KJ/mol IE1 IE2 IE3 IE4 IE5 (MJ/mol) (MJ/mol) IE6 IE7 IE8 (MJ/mol) (MJ/mol) (MJ/mol) (MJ/mol) (MJ/mol) (MJ/mol) 0.744 1.457 7.739 10.547 13.636 18.001 1.687 3.381 6.057 8.414 11.029 15.171 1.093 2.359 4.627 6.229 37.838 47.285 0.906 1.763 14.855 21.013 group 21.710 25.663 17.874 92.047 IE3 and IE4 is more different , why ? 125 angka teprattananan Trends in First Ionization Energies of First 20 Elements angka teprattananan 126 Trends in First Ionization Energies of Elements First ionization energy tends to increase from bottom to top within a group. And increase from left to right across a period. However, there are two apparent discontinuities in this trend. angka teprattananan 127 angka teprattananan 128 Electron Affinity(EA) 1. Which element in each pair has the greater ionization energy? 1. 12Mg or 13Al 2. 4Be or 5B 3. 6C or 14Si Electron affinity is the energy change when an atom gains one electron. Where ionization energy is always endothermic, electron affinity is usually exothermic, but not always. 4. 2He or 53I 2. Arrange these atoms in order of increasing IE1 ? 33As , 37Rb , 18Ar , 15P , 16S Example ; 3. Arrange these atoms in order of increasing IE1 ? 19K , 13Al , 11Na , 12Mg , 20Ca angka teprattananan 129 in Electron affinity of Elements If the atom has more tendency to accept an electron then the energy released will be large and electron affinity will be high. Atoms with large ionization energy have negative electron affinity. If there are no empty spaces, a new orbital, making the process endothermic (Group IIA and VIIIA). e.g. 2 2 6 2 Group IIA 12Mg : 1s 2s 2p 3s 2 2 6 2 6 Group VIIIA 18Ar : 1s 2s 2p 3s 3p angka teprattananan 131 O(g) + e O-(g) + e O- (g) : EA = -142 KJ/mol O2- (g) : EA = 780 KJ/mol 130 angka teprattananan Trends in Electron Affinity angka teprattananan 132 Electronegativity (EN) 1. Which element in each pair has the greater electron affinity? 1. 12Mg or 13Al 2. 3Li or 8O 3. 6C or 5. 11Na or 32Ge 19K 4. 18Ar Electronegativity is the tendency for an atom to attract electrons to itself when it is chemically combined with another element. High electronegativity means it pulls the electron toward it. or 53I 6. 9F or 53I 2. Arrange these atoms in order of increasing EA ? 19K , 20Ca , 11Na , 15P , 9F 133 angka teprattananan 6.3 Trends in Electronegativity of Elements Electronegativity tends to increase from bottom to top within a group. And increase from left to right across a period. Because the increase of nucleus attraction. Note; Noble gases are NOT assigned electronegativities angka teprattananan angka teprattananan 134 Trends in Electronegativity Representative Elements in Groups 1A through 7A 135 angka teprattananan 136 1. Which element in each pair has the greater electronegativity? 1. 11Na or 15P 2. 3Li or 8O 4. 9F or 53I 3. 6C or 32Ge 2. Draw arrow to show the bond polarity in each pair elements N---F C---Br O----Cl Br---Br C---S C----I 3. Arrange these atoms in order of increasing EN ? 12Mg , 20Ca , 17Cl , 9F 137 angka teprattananan For metals ; The melting point and boiling point tends to increase from bottom to top within a group (the increase metallic bond). Melting Point and Boiling Point The melting point is the temperature at which the transition from the solid phase to the liquid phase. - Helium has the lowest melting point (-272.2oC). - Carbon has the highest melting point (3550oC). The boiling point is the temperature at which the transition from the liquid to the gas phase. - Helium has the lowest boiling point (-268.9oC). - Tungsten has the highest boiling point (5927oC). angka teprattananan 138 For nonmetals ; The melting point and boiling point tends to increase from top to bottom within a group. And increase from right to left across a period. (the increase van der waals' forces) And increase from left to right across a period (the metallic bond increase when increase of outer electrons or valence electron). But, the group IVA ; high melting point and boiling point because they have giant molecules(Network structure). angka teprattananan 139 angka teprattananan 140 Arrange these atoms in order of increasing melting boiling point ? Electron affinity 17Cl , 13Al 11Na , 3Li 4. 9F , 53I , 11Na 5. 7N , 14Si , 9F , m.p. and b.p. of metal , 13Al 10Ne 141 angka teprattananan Oxidation number angka teprattananan Atomic radius metallic character m.p. and b.p. of nonmetal142 3. The oxidation number of some elements in their compounds is fixed E.g. Hydrogen in most of its compound = +1 Oxygen in most of its compound = -2 all group I elements = +1 all group II elements = +2 4. The sum of the oxidation numbers of the elements in a molecule or ion is equal to the charge on the molecule or ion. E.g. OH- (-2) + (+1) = -1 The oxidation number of an element indicates the number of electrons lost, gained, or shared as a result of chemical bonding. Rules of Oxidation Number 1. Elements have an oxidation number of zero. E.g. Na , K , Pb , H2 , O2 , P4 2. The oxidation number of simple ion is the charge on the ion. E.g. Li+ = +1 , Fe3+ = +3 , O2- = -2 , Cl- = -1 angka teprattananan m.p. and b.p. of metal 10Ne Electronegativity metallic character 3. 6C , Ionization energy Atomic radius 2. 3Be , , Electronegativity 15P Electron affinity , Ionization energy 19K summary m.p. and b.p. of nonmetal 1. Periodic trends 143 angka teprattananan 144 Determine the oxidation number of underline element : Find the Oxidation Number of S in SOCl4 ? O.N. of Oxygen = O.N. of Chlorine = 1. SO2 2. CaSO4 3. PO434. NH4+ Oxidation numbers of C in HCO3- ? 5. Pb(OH)4 HCO3O= 6. KMnO4 H= 7. Cu(NO3) 8. K2[Fe(CN)3H2O] angka teprattananan 145 Determine the oxidation number of underline element : 3. SO3 1. CO 2. CH4 4. Al2O3 5. S2Cl2 6. BaSO4 7. MgCrO4 8. Sr(NO3)2 9. IF3 10. K2MnO4 11. [Fe(CN)6]3- 12. Cr(OH)3 13. NiCl2.6H2O 14. K3[Fe(CN)6] 15. [Cu(NH3)4]SO4 16. [Mn(H2O)6]3+ 17. (NH4)2[NiCl4] angka teprattananan 147 angka teprattananan 146