Calculate the mass of magnesium oxide which would be obtained by burning 120 g of magnesium in air.

Explanation

To calculate the mass of magnesium oxide (MgO) produced by burning 120 g of magnesium (Mg) in air, we can follow these steps:

### Step 1: Write the balanced chemical equation
The reaction of magnesium burning in air can be represented as:
\[ 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \]
This equation shows that 2 moles of magnesium react with 1 mole of oxygen to produce 2 moles of magnesium oxide.
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