One litre of oxygen at NTP weighs 1.46 g. How many litres of oxygen are needed for the combustion of `21.0` g of Mg whose equivalent weight is `1/2` mole?

Explanation

To solve the problem step by step, we need to find out how many liters of oxygen are required for the combustion of 21.0 g of magnesium (Mg).

### Step 1: Determine the equivalent weight of magnesium (Mg)
The equivalent weight of magnesium is given as \( \frac{1}{2} \) mole. Since the molar mass of magnesium is approximately 24 g/mol, we can calculate the equivalent weight as follows:

\[ \text{Equivalent weight of Mg} = \frac{\text{Molar mass}}{n} \]
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