Question

In a titration between oxalic acid and acidified potassium permanganate, the manganous salt is formed which catalyses the reaction. The manganous salt is

• A. An auto catalyst
• B. A positive catalyst
• C. A promoter
• D. Inhibitor

Answer 1

The correct option is A

An auto catalyst

When KMNO₄ solution is added to oxalic acid, the disappearance of pink colour is slow at start but as soon as some Mn²⁺ ions are formed the disappearance of pink colour becomes rapid this shows that Mn²⁺ ions are autocatalyst.