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?

Answer 1

According to the law of conservation of mass, the mass of the reactants must equal the mass of the products in a chemical reaction. In this case, you have:

• Mass of magnesium (Mg) = 24 grams
• Mass of oxygen (O₂) = 16 grams

To find the total mass of magnesium oxide (MgO) formed after the reaction, you simply add the mass of magnesium to the mass of oxygen:

$$\text{Total mass of reactants}=\text{Mass of magnesium}+\text{Mass of oxygen}=24,\text{grams}+16,\text{grams}=40,\text{grams}$$

Therefore, according to the law of conservation of mass, the mass of magnesium oxide produced will be 40 grams after the chemical change is complete.