Assertion: `HClO_(4)` is a stronger acid than `HClO_(3)`.
Reason: Oxidation state of `Cl` in `HClO_(4)` is `+VII` and in `HClO_(3)+V`.

Options

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

Answer

B

Explanation

Both assertion and reason are true but reason is not the correct explanation of assertion. Greater the number of negative atoms present in the oxy-acid make the acid stronger. In general, the strength of acids that have general formula `(HO)_(m)ZO_(n)` can be related to the value of n. As the value of n increases, acidic character also increases. The negative atoms draw electrons away from the Z-atom and make it more positive. The Z-atom, therefore, becomes more effective in with drawing electron density away from the oxygen atom that bonded to hydrogen. in turn, the electrons of `H-O` bond are drawn more strongly away from the H-atom. The net effect makes it easier from the proton release and increases the acid strength.