Question

The stability of a solute decreases with increase in temperature if dissolution is________.​

Answer 1

The solubility of a solute decrease with temperature when dissolution is exothermic.

e.g., CaCl

2

,Ca(OH)

2

,(CH

3

COO)

2

Ca,NaOH,KOH etc.

Ca(OH)

2

(s)+aq→Ca(OH)

2

(aq)+Qkcal.

Since heat is evolved, with increase in the temperature, the equilibrium shifts in the reverse direction so as to nullify the effect of increased temperature. Hence, the solubility decreases.