Acid hydrolysis of sucrose is a

Options

A. pseudo firs order reaction
B. zero order reaction
C. second order reaction.
D. unimolecular raction.

Explanation

To solve the question regarding the acid hydrolysis of sucrose, we will analyze the reaction step by step.

### Step 1: Understanding the Reaction
The acid hydrolysis of sucrose involves the breakdown of sucrose into its constituent monosaccharides, glucose and fructose. The reaction can be represented as:

\[ \text{sucrose} + \text{H}_2\text{O} \xrightarrow{\text{H}^+} \text{glucose} + \text{fructose} \]

### Step 2: Rate of Reaction
The rate of a chemical reaction is generally expressed in terms of the concentrations of the reactants. For the hydrolysis of sucrose, the rate law can be written as:

\[ \text{Rate} = k [\text{sucrose}][\text{H}_2\text{O}] \]

where \( k \) is the rate constant.

### Step 3: Concentration of Water
In the case of acid hydrolysis, water is typically present in a large excess compared to sucrose. This means that the concentration of water remains relatively constant throughout the reaction.

### Step 4: Pseudo First Order Reaction
Since the concentration of water does not change significantly during the reaction, we can treat it as a constant. Therefore, we can define a new rate constant \( k' \) as follows:

\[ k' = k [\text{H}_2\text{O}] \]

Now, the rate law simplifies to:

\[ \text{Rate} = k' [\text{sucrose}] \]

This indicates that the reaction behaves as a first-order reaction with respect to sucrose, even though it involves two reactants. Hence, the reaction is classified as a pseudo first-order reaction.

### Conclusion
The acid hydrolysis of sucrose is a pseudo first-order reaction.

### Final Answer
The correct option is: **Pseudo first-order reaction.**

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