The strength of 20 volume of `H_2 O_2` is

Explanation

To determine the strength of 20 volume hydrogen peroxide (H₂O₂), we can follow these steps:

### Step 1: Understand the Concept of Volume Strength
The volume strength of a solution indicates the volume of gas produced at NTP (Normal Temperature and Pressure) when 1 liter of the solution decomposes. For hydrogen peroxide, 1 volume strength corresponds to 1 liter of oxygen gas produced from 1 liter of H₂O₂.

### Step 2: Write the Decomposition Reaction
The decomposition of hydrogen peroxide can be represented as:
\[ 2 \text{H}_2\text{O}_2 \rightarrow 2 \text{H}_2\text{O} + \text{O}_2 \]
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