Question
Among the following oxoacids, the correct decreasing order of acid strength is:
A.
$$HOCl > HCl{O_2} > HCl{O_3} > HCl{O_4}$$
B.
$$HCl{O_4} > HOCl > HCl{O_2} > HCl{O_3}$$
C.
$$HCl{O_4} > HCl{O_3} > HCl{O_2} > HOCl$$
D.
$$HCl{O_2} > HCl{O_4} > HCl{O_3} > HOCl$$
Answer :
$$HCl{O_4} > HCl{O_3} > HCl{O_2} > HOCl$$
Solution :
Acidic strength increases as the oxidation number of
central atom increases. Hence acidic strength order is
$$\mathop {HCl{O_4}}\limits^{\left( { + 7} \right)} > \mathop {HCl{O_3}}\limits^{\left( { + 5} \right)} > \mathop {HCl{O_2}}\limits^{\left( { + 3} \right)} > \mathop {HClO}\limits^{\left( { + 1} \right)} $$