Question

Acid hydrolysis of sucrose is a

• A. pseudo first order reaction
• B. zero order reaction
• C. second order reaction
• D. unimolecular reaction

Answer 1

Answer: (A)

pseudo first order reaction

Answer 2

It is an example of pseudo unimolecular reaction where molecularity $\geq 2$ but order of reaction is one. Rate $=k[$ Sugar $]\left[ H _{2} O \right]$ In the reaction, water is present in excess and its concentration is taken to be constant, thus the reaction becomes independent of $\left[ H _{2} O \right]$ and is pseudo first order.