Final answer:
To produce 10g of magnesium oxide, 6g of magnesium would be needed.
Step-by-step explanation:
To find the mass of magnesium needed to produce 10g of magnesium oxide, we can use the given information about the reaction between magnesium and oxygen. From the given information, we know that when 24g of magnesium is heated in air, 40g of magnesium oxide is produced. This means that the reaction produces a 1:1 ratio between the mass of magnesium and the mass of magnesium oxide. Therefore, if 24g of magnesium produces 40g of magnesium oxide, then 10g of magnesium oxide would require (10g/40g) * 24g = 6g of magnesium.