Question

The correct statement(s) about the oxoacids, $HCl{O}_4$ and $HClO$, is(are):

• A. the central atom in both $HCl{O}_4$ and $HClO$ is $s{p}^3$ hybridized
• B. the conjugate base of $HCl{O}_4$ is weaker base than $H_{2}O$
• C. $HCl{O}_4$ is formed in the reaction between ${Cl}_2$ and $H_{2}O$
• D. $HCl{O}_4$ is more acidic than $HClO$ because of the resonance stabilization of its anion

Answer 1

Answer: (A), (B), (D)

The correct options are
A the central atom in both $HCl{O}_4$ and $HClO$ is $s{p}^3$ hybridized
B the conjugate base of $HCl{O}_4$ is weaker base than $H_{2}O$
D $HCl{O}_4$ is more acidic than $HClO$ because of the resonance stabilization of its anion

The correct statement(s) about the oxoacids, $HCl{O}_4$ and $HClO$, are the following
(A) The central atom in both $HCl{O}_4$ and $HClO$ is $s{p}^3$ hybridized. The central $Cl$ atom in $HCl{O}_4$ has 4 bonding domains and zero lone pairs of electrons.
The central $O$ atom in $HClO$ has 2 bonding domains and 2 lone pairs of electrons.
(B) The conjugate base of $HCl{O}_4$ is weaker base than $H_{2}O$. This is because $HCl{O}_4$ is stronger acid than water. A stronger acid has weaker conjugate base and vice versa.
(D) $HCl{O}_4$ is more acidic than $HClO$ because of the resonance stabilization of its anion. Greater is the extent of delocalisation, greater is the stabilisation of negative charge and higher is the acidity. In $HCl{O}_4$, negative charge is delocalised over $4O$ atoms.
The following statement is incorrect.

(C) $HCl{O}_4$ is formed in the reaction between $C{l}_2$ and $H_{2}O$."
Instead, the following methods are used.
$NaCl{O}_4+HCl\to NaCl+HCl{O}_4$
Laboratory preparations of $HCl{O}_4$ include the following
Treatment of barium perchlorate with sulfuric acid to give barium sulfate and perchloric acid.
Nitric acid is mixed with ammonium perchlorate to form nitrous oxide and perchloric acid