These questions consist of two statements each, printed as Assertion and Reason. While answering these questions you are required to choose any one of the following four responses:
Assertion: `[Al(H_2O)_6]^(3+)` is a stronger acid than `[Mg(H_2O)_6]^(2+)`.
Reason: Size of `[Al(H_2O)_6]^(3+)` is smaller than `[Mg(H_2O)_6]^(2+)` and posseses more effective nuclear charge.

Options

A. If both assertion and reason are true, but reason is not the true explanation of the assertion
B. If both assertion and reason are true, but reason is not the true explanation of the assertion
C. If assertion is true, but reason is false
D. If both assertion and reason are false

Answer

A

Explanation

R is the correct explanation of A. This is because `[Al(H_(2)O)_(6)]^(3+)` has greater effective nuclear charge than `[Mg(H_(2)O)_(6)]^(2+)` and thus attracts electron pairs from donor groups more effectively. This also makes it relatively more acidic.