Percent Composition by Mass

• Total Molar Mass of Element in Compound
• Total Molar Mass of Compound
• Molar Mass of a Single Element
• 100

• 27.3%

• 42.9%

• 57.1%

• 72.7%

If a compound sample contains 40g of calcium, 12g of carbon, and 48g of oxygen, what is the percent composition by mass of calcium?

• 40%

• 50%

• 60%

• 70%

• 11%

• 89%

• 67%

• 33%

A compound contains 24g of carbon, 4g of hydrogen, and 32g of oxygen. What is the percent composition by mass of hydrogen?

• 4%

• 7%

• 12%

• 14%

If a compound sample has a total mass of 180 grams and is composed of 40% carbon, 6.7% hydrogen, and 53.3% oxygen, what is the mass of oxygen in the compound?

• 72 g

• 96 g

• 108 g

• 120 g

Tags

NGSS.HS-PS1-7

• The Molar Mass of Sulfur in Sulfuric Acid

• The Molar Mass of Sulfuric Acid

• The number of atoms in the sample.

• The volume of the sample.

Tags

NGSS.HS-PS1-7

A sample of a compound contains 9.0 g of aluminum, 28.0g of sulfur, and 64.0g of oxygen. What is the percent composition by mass of sulfur in the compound?

• 20%

• 28%

• 30%

• 33%

• 82.2%

• 77.4%

• 70.0%

• 67.9%

If a sample has a mass of 58.5 grams and is composed of 39.3 g of Na, 18.6 g of C, and 0.6 g of H, what is the percent composition by mass of carbon?

• 31.8%

• 33.3%

• 35.7%

• 37.6%