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)

It is an example of pseudo unimolecular reaction where molecularity $\ge 2$ 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.