1	Ionic Bonds and Main Group Chemistry Chapter 6
2	Ionization Energy The amount of energy required to remove the outermost electron form an isolated neutral atom in the gaseous state.
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5	Higher ionization energies Ionization energy always increases as you pull off more electrons. Ionization energies take a huge leap when we try to remove an electron from a new inner shell.
6	Electron Affinity The energy change that occurs when an electron is added to an atom (or ion) in the gaseous state. Frequently costs nothing but actually yields energy therefore EA’s are usually negative.
7	Ionic Bonds Ions are held together by ionic attraction where the force of attraction is governed by Coulomb’s Law. Makes sense Large Z ® strong attraction ® larger E Large d ® charge felt less ® smaller E
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10	Formation of ionic compounds Get elements as atoms (generally requires energy) Form ions (anions are energetically favorable, cations are unfavorable) Bring ions together (favorable) Condense to solid phase (favorable)
11	Energetics of NaCl Formation Na(s) ¾®Na(g) +107.3 kJ/mol Na(g) ¾® Na⁺ + 1e^- +495.8 kJ/mol 1/2 Cl₂(g) ¾® Cl (g) +122 kJ/mol Cl(g) ¾® Cl^-(g) -348.6 kJ/mol Na⁺(g) + Cl^-(g) ® NaCl(s) -787 kJ/mol ==================================== Na(s) + 1/2 Cl₂(g) ¾® NaCl(s) -411 kJ/mol
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13	"Determine the energy of formation..." Determine the energy of formation of MgCl₂ from the elements.
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17	magnesium bromide Mg(s) ¾® Mg(g) +147.7 kJ/mol Mg(g) ¾® Mg⁺ + 1e^- +737.7 kJ/mol Mg⁺(g) ¾® Mg²⁺(g) + 1e^- +1450.7 kJ/mol Br₂(g) ¾® 2 Br (g) +193 kJ/mol 2Br(g) ¾® 2Br^-(g) 2(-325 kJ/mol) = -650 kJ/mol Mg²⁺(g) + 2Br^-(g) ® MgBr₂(s) -2440 kJ/mol ==================================== Mg(s) + Br₂(g) ¾® MgBr₂(s) - 561 kJ/mol
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19	"Calculate the energy released in..." Calculate the energy released in kJ/mol in the reaction Na(s) + 1/2 I₂(s) ¾® NaI(s) The energy of vaporization of Na(s) is 107 kJ/mol. The sum of the enthalpies of dissociation and vaporization of I₂(s) is 214 kJ/mol, and the lattice energy of NaI is 704 kJ/mol.
20	"Calculate the energy released in..." Calculate the energy released in kJ/mol when LiH is formed in the reaction Li(s) + ½ H₂(g) à LiH(s) Heat of vaporization, Li 161 kJ/mol Dissociation energy, H₂ 436 kJ/mol Lattice energy, LiH -917 kJ/mol Ionization energy, Li 520 kJ/mol Electron affinity, H -73 kJ/mol Answer: -91 kJ/mole net change
21	Descriptive Chemistry Alkali Metals Alkaline Earths Aluminum Halogens Nobel Gases