Thermodynamic data for three salts are listed below
CHEMISTRY · Single correct · A Level · Chemistry · Thermodynamics · Thermodynamics
Problem
Thermodynamic data for three salts are listed below. Positive lattice enthalpy values correspond to the energy required to separate the ions; negative hydration enthalpy values correspond to the energy released when the ions are solvated.
Salt Lattice enthalpy (kJ mol⁻¹) Hydration enthalpy (kJ mol⁻¹)
A +787 −799
B +910 −865
C +650 −700
Assuming the three salts have comparable standard entropy changes on dissolving, which salt is predicted to have the most negative standard free energy of dissolution at 298 K?
(a) Salt A
(b) Salt C
(c) Salt B
(d) The three salts are predicted to have identical free energies