SOLVED

71) Use the data given below to construct a Born-Haber cycle to determine the heat of formation of KCl. DH°(kJ) K(s) → K(g)89 K(g) → K?(g) + e?418 Cl2(g) → 2 Cl(g)244 Cl(g) + e? → Cl?(g)-349 KCl(s) → K?(g) + Cl?(g)717 A) -1119 kJ B) -997 kJ C) -437 kJ D) +631 kJ E) +158 kJ 72) Use the data given below to construct a Born-Haber cycle to determine the bond energy of O2. DH°(kJ) Na(s) → Na(g)107 Na(g) → Na?(g) + e?496 O(g) + e? → O?(g)-141 O?(g) + e? → O2?(g)878 2 Na(s) + O2(g) → Na2O(s)-416 2 Na?(g) + O2?(g) → Na2O(s)-2608 A) 426 kJ B) 249 kJ C) 852 kJ D) 498 kJ E) 356 kJ 73) Use the data given below to construct a Born-Haber cycle to determine the second ionization energy of Ca. DH°(kJ) Ca(s) → Ca(g)193 Ca(g) → Ca?(g) + e?590. 2 O(g) → O2(g)-498 O(g) + e? → O?(g) -141 O?(g) + e? → O2?(g)878 Ca(s) + O2(g) → CaO(s)-635 Ca2?(g) + O2?(g) → CaO(s)-3414 A) 1010 kJ B) 1757 kJ C) 1508 kJ D) -3027 kJ E) -1514 kJ 74) When drawing out Lewis structures, how many electrons surround the most stable element? A) 1 B) 3 C) 6 D) 8 E) 10 75) The energy associated with formation of a crystalline structure from gaseous ions is know as the A) ionization energy. B) lattice energy. C) precipitation energy. D) electron affinity. E) potential energy. 76) What is the formula for zinc chloride? A) ZnC B) Zn2Cl2 C) ZnCl2 D) Zn2Cl E) ZnCl3 77) What is the formula for calcium phosphate? A) CaP B) Ca2P3 C) Ca2(PO4)3 D) Ca3(PO4)2 E) CaPO4 78) What is the chemical name for P2I4? A) phosphorous (IV) iodine B) diphosphorous tetraiodine C) phosphorous tetraiodine D) phosphorous (II) iodine E) diphosphorous iodine 79) A compound was isolated and found to contain 72.2% magnesium and the rest nitrogen. What is the empirical formula of this compound? A) Mg3N2 B) MgN3 C) MgN D) Mg2N3 E) Mg3N 80) Dioxybenzone is a compound found in sunscreen, and only contains carbon, oxygen, and hydrogen.  Analysis of the compound found that it contains 4.92% hydrogen and 26.18% oxygen. The molar mass of the compound is 244.25 g/mol. What is the molecular formula? A) C12H10O3 B) C10H8O4 C) C8H11O5 D) C14H12O4 E) C16H10O6 81) What is the empirical formula for a compound that undergoes combustion analysis and produces 12.32g of CO2 and 6.71g of H2O? A) C3H4 B) C4H7 C) C3H8 D) CH4 E) C2H3