Question

Why H2SO4 is strong acid than H2SO3?

Why HClO2 is strong acid than HClO?

Why HClO is strong acid than HBrO?

Why CCl3COOH is strong acid thn CH3COOH?

Please explain the reasons.

Answer 1

Solution.

a) Compaiting two similar acids with different number of oxygen atoms, the stronger is the acid with a greater oxidation number of a central atom. The oxidation number of S in H₂SO₄ is +6, and  the oxidation number of S in H₂SO₃ is +4, therefore, H₂SO₄ is the stronger acid.

b) HClO₂ and HClO are also two similar acids with different number of oxygen atoms. The oxidation number of Cl in HClO₂ is +3, and  the oxidation number of Cl in HClO is +1, therefore, HClO₂ is the stronger acid.

c) The acidity of the oxygen-containing acids is decreasing going down the group of periodic table. Cl is above Br, but they are in the same group, therefore, HClO is a stronger acid than HBrO.

d) The CCl₃COOH is stronger than CH₃COOH due to the inductive effect of -Cl atoms, which stabilize the conjugated base anoin, making hte acid stronger.