Given below are two statements:
Statement I: None of the alkaline earth metal hydroxides dissolves in alkali.
Statement II: Solubility of alkaline earth metal hydroxides in water increases down the group.
In the light of the above statements, choose the most appropriate answer from the options given below:
Statement I: None of the alkaline earth metal hydroxides dissolves in alkali.
Statement II: Solubility of alkaline earth metal hydroxides in water increases down the group.
In the light of the above statements, choose the most appropriate answer from the options given below:
- (A)Statement I and Statement II both are incorrect.
- (B)Statement I is incorrect but Statement II is correct.✓ Correct
- (C)Statement I is correct but Statement II is incorrect.
- (D)Statement I and Statement II both are correct.
Answer: (B)
Solution
Beryllium hydroxide is amphoteric: being the hydroxide of the smallest and most polarising of the group 2 cations it dissolves in excess sodium hydroxide to give the beryllate ion , so it is untrue that no alkaline earth hydroxide dissolves in alkali. Going down the group the lattice enthalpy of the hydroxides falls faster than the hydration enthalpy of the cation, so solubility in water rises from sparingly soluble to freely soluble . Statement I is incorrect but Statement II is correct.
JEE Main · 2021 · 25 Jul 2021 · Shift 1 · Single correct option