For the reaction :
` A +H_2 O to B` rate ` prop [A]` what is its
order of reaction ?

Explanation

To determine the order of the reaction given by the equation:

\[ A + H_2O \rightarrow B \]

with the rate of reaction being directly proportional to the concentration of A, we can follow these steps:

### Step 1: Understand the Rate Law Expression
The rate of a reaction can be expressed in terms of the concentrations of the reactants. In this case, we are given that the rate is directly proportional to the concentration of A. This can be written as:
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