Calculate the amount per litre of 10 mL of a solution of hydrogen peroxide labelled 20 volumes.

Explanation

To solve the problem of calculating the amount of hydrogen peroxide in a 10 mL solution labelled as 20 volumes, we will follow these steps:

### Step 1: Understand the meaning of "20 volumes"
The term "20 volumes" means that 1 liter of the hydrogen peroxide solution can produce 20 liters of oxygen gas (O2) when decomposed.

### Step 2: Write the decomposition reaction
The decomposition of hydrogen peroxide (H2O2) can be represented by the following reaction:
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