Question

When a 13.60-g sample of a compound containing only magnesium

and oxygen is decomposed, 5.40 g of oxygen is obtained. What is the
percent composition of this compound?

Answer 1

To determine the percent composition of the compound, subtract the mass of oxygen obtained from the total mass of the compound. Then calculate the percent composition using the mass of magnesium and the total mass of the compound.

Step-by-step explanation:

To determine the percent composition of the compound, we need to find the mass of magnesium in the compound. We know that the total mass of the compound is 13.60 g and the mass of oxygen obtained is 5.40 g. Therefore, the mass of magnesium is 13.60 g - 5.40 g = 8.20 g.

Now, we can calculate the percent composition:

Percent composition of magnesium = (mass of magnesium / total mass of compound) * 100%

Percent composition of magnesium = (8.20 g / 13.60 g) * 100% = 60.29%

The percent composition of the compound is 60.29% magnesium and 39.71% oxygen.