Calculating Percent Composition

What is the percent composition of carbon in carbon dioxide (CO2)?

• 27.3%

• 44.0%

• 12.0%

• 72.7%

If a compound is made of 40% sulfur and 60% oxygen by mass, what is the percent composition of sulfur?

• 40%

• 60%

• 50%

• 30%

A sample contains 10 grams of hydrogen and 90 grams of oxygen. What is the percent composition of hydrogen?

• 10%

• 90%

• 11.1%

• 8.9%

Which of the following is the correct formula to calculate percent composition?

• (mass of element/mass of compound) x 100

• (mass of compound/mass of element) x 100

• (mass of element/mass of compound) x 10

• (mass of compound/mass of element) x 10

In a 100g sample of water, how many grams of oxygen are present if the percent composition of oxygen is 88.8%?

• 88.8g

• 11.2g

• 50g

• 44.4g

Tags

NGSS.MS-PS1-1

What is the percent composition of hydrogen in water (H2O)?

• 11.2%

• 88.8%

• 5.6%

• 44.4%

Tags

NGSS.MS-PS1-1

A compound has a molar mass of 180 g/mol and contains 72 g of carbon. What is the percent composition of carbon?

• 40%

• 60%

• 50%

• 30%

If a compound is composed of 20% nitrogen and 80% oxygen, what is the percent composition of oxygen?

• 80%

• 20%

• 50%

• 60%

Which element has the highest percent composition in the compound NaCl?

• Sodium

• Chlorine

• Both have equal composition

• Cannot be determined

A mineral sample contains 30% iron and 70% sulfur. What is the percent composition of sulfur?

• 70%

• 30%

• 50%

• 60%