Question

Select the correct order for the given properties.

• A. Thermal stability : $BeC{O}_3<MgC{O}_3<CaC{O}_3$
• B. Solubility : $BeC{O}_3>MgC{O}_3>CaC{O}_3$
• C. Thermal stability : $L{i}_{2}S{O}_4<N{a}_{2}S{O}_4<K_{2}S{O}_4$
• D. None of the above.

Answer 1

Answer: (A), (B), (C)

The correct options are
A Thermal stability : $L{i}_{2}S{O}_4<N{a}_{2}S{O}_4<K_{2}S{O}_4$
B Solubility : $BeC{O}_3>MgC{O}_3>CaC{O}_3$
C Thermal stability : $BeC{O}_3<MgC{O}_3<CaC{O}_3$

(A) The thermal stability of the alkaline earth metal carbonates increases in the order $BeC{O}_3<MgC{O}_3<CaC{O}_3$.

The metal ions with bigger atomic size form stable carbonates and bicarbonates.
Thus, the option A is correct.
(B) The solubility of alkaline earth metal carbonates decreases in the order $BeC{O}_3>MgC{O}_3>CaC{O}_3$.
With increase in the size of the cation, the hydration enthalpy decreases and the solubility decreases.
Thus, the option B is correct.
(C) Thermal stability of the alkali metal carbonates increases in the order $L{i}_{2}S{O}_4<N{a}_{2}S{O}_4<K_{2}S{O}_4$.
The metal ions with bigger atomic size form stable sulphates. Thus, the option C is correct