Ionic EquilibriumHard

Question

On dissolving a substance in water, it can produce either an ionic or molecular solution. From the following data, predict what type of solution is likely to be formed by CaCl2 and HgCl2 at 25°C?

The maximum contribution of T∆S in dissolution process is 30 kJ at 25°C

Options

A.both ionic.
B.both molecular.
C.CaCl2 is ionic but HgCl2 is molecular.
D.CaCl2 is molecular but HgCl2 is ionic.

Solution

For molecular solubility of CaCl2,

ΔHsolution = 209.2 + (–33.5) = 175.7 KJ > 30 KJ

For ionic solubility of CaCl2,

ΔHsolution = 209.2 + 1004.2 + 1715.4 – 1598.3 – 719.6 – 711.2 = – 100.3 KJ

For molecular solubility of HgCl2,

ΔHsolution = 83.7 – 66.9 = 16.8 KJ < 30 KJ

For ionic solubility of HgCl2,

ΔHsolution = 83.7 + 460.2 + 2815.8 – 1845.1 – 719.6 – 711.2 = 83.3 KJ > 30 KJ

Hence, CaCl2 is ionic and HgCl2 is molecular solubility.

Create a free account to view solution

View Solution Free
Topic: Ionic Equilibrium·Practice all Ionic Equilibrium questions

More Ionic Equilibrium Questions

An amount of 2.0 M solution of Na2CO3 is boiled in a closed container with excess of CaF2. Very little amount of CaCO3 a...0.1mol HCl is dissolved in distilled water of volume V then at limV&#8594;&#8734; (pH)solution is equal to...M(OH)x has KSP 4 &#215; 10-12 and solubility 10-4 M. The value of x is:...Which of the following buffers have a pH greater than 7 ?(a) AgOH + AgBr(b) CH3COOH + CH3COONa(c) Mg(OH)2 + Mg(OH)Cl(d) ...When different types of salts have nearly same solubility product constant KSP which are less than one. The most soluble...