Passage IV (Questions 25-28)

An investigator studies several properties related to silver and chlorine and to their salt, AgCl:

Experiment 1. The investigator determines the first ionization energy, HiE, of gas-phase Ag:

Ag(g) --> Ag+ + e- HiE = 728 kJ/mol

Experiment 2. The investigator determines the heat of sublimation of solid silver:

Ag(s) --> Ag(g) Hsubl = 286 kJ/mol

Experiment 3. Next, the investigator determines the dissociation energy of diatomic chlorine, Cl:

Cl2(g) --> 2Cl(g) Hdiss = 239 kJ/mol

Experiment 4. The investigator finds the solubility product of solid AgCl in water:

AgCl(s) = Ag+ (aq) + Cl-(aq) Ksp = 1.8 x10-10

Experiment 5. Finally, the investigator measures the value of the heat of formation of AgCl:

Ag(s) + 1/2 Cl2 --> AgCl(s) Hf = -128 kJ