Question

Verify the following chemical equation is balanced.

2Mg + O₂ → 2MgO
With 0.5 moles of O₂, how many moles of Mg would be needed to react? (Write only the number of moles in the blank to answer the question! For example, write 3 not 3 moles.)

Answer 1

To react with 0.5 moles of O₂, 1 mole of Mg would be needed according to the balanced chemical equation 2Mg + O₂ → 2MgO.

Step-by-step explanation:

The chemical equation 2Mg + O₂ → 2MgO is indeed balanced; it reflects that two moles of magnesium react with one mole of oxygen to produce two moles of magnesium oxide. When you have 0.5 moles of O₂, you would need double the amount of magnesium because each molecule of O₂ (which consists of two oxygen atoms) reacts with two atoms of Mg.

Therefore, the calculation is straightforward:
Number of moles of Mg needed = 2 × (Number of moles of O₂) = 2 × 0.5 = 1 mole of Mg.