Determine the order of reaction :
Step 1. `2NO+H_2 to N_2+H_2O_2` Slow
Step 2. `H_2O_2 + H_2 to 2H_2O` Fast

Explanation

To determine the order of the reaction given the two steps, we will follow these steps:

### Step 1: Identify the Slow Step
The first step of the reaction is:
\[ 2NO + H_2 \rightarrow N_2 + H_2O_2 \] (Slow step)

The second step is:
\[ H_2O_2 + H_2 \rightarrow 2H_2O \] (Fast step)
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