Twenty-four grams of magnesium metal reacts with sixteen grams of oxygen gas to form magnesium oxide. According to the law of conservation of mass, how much magnesium oxide will there be after the chemical change is complete?

Question

A.
16 g
B.
24 g
C.
30 g
D.
40 g

Answer 1

According to the law of conservation of mass, the total mass of the reactants must equal the total mass of the products in a chemical reaction.

In this case, the reactants consist of:

• Magnesium: 24 grams
• Oxygen: 16 grams

To find the total mass of the reactants, we add these amounts together:

Total mass of reactants = mass of magnesium + mass of oxygen
Total mass of reactants = 24 g + 16 g = 40 g

Since the law of conservation of mass states that mass is neither created nor destroyed, the mass of the magnesium oxide produced will also be 40 grams.

Therefore, the answer is:

D. 40 g