Question

Assertion (A): H₂S is less acidic than H₂Te.

Reason (R): H-S bond has more Δ_bond H° than H-Te bond.

Options

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true but R is not the correct explanation of A.

• A is true but R is false.

• A is false but R is true.

Answer 1

Both A and R are true but R is not the correct explanation of A.

Explanation:

The acidity of hydrides increases down the group because the bond strength between hydrogen and the central atom decreases, making it easier to release H⁺. In H₂S the H - S bond has a higher bond dissociation enthalpy (Δ_bond H°) compared to the weaker H - Te bond in H₂Te which makes H₂Te more acidic. Hence, the reason correctly explains the assertion.