Mass Percent Composition Quiz

What is the first step in calculating the mass percent composition of an element in a compound?

• Multiply the mass of the element by 100.

• Subtract the mass of the element from the total mass of the compound.

• Add the masses of all elements in the compound.

• Divide the mass of the element by the total mass of the compound.

How do you express the mass percent composition as a percentage?

• Subtract 100.

• Multiply by 100.

• Divide by 100.

• Add 100.

What is the molar mass of carbon used in the calculation for CO2?

• 18.02 g/mol

• 14.01 g/mol

• 12.01 g/mol

• 16.00 g/mol

How many carbon atoms are present in one mole of CO2?

• Three

• One

• Two

• Four

What is the molar mass of oxygen used in the calculation for CO2?

• 16.00 g/mol

• 14.01 g/mol

• 12.01 g/mol

• 18.02 g/mol

How many oxygen atoms are present in one mole of CO2?

• Two

• Three

• One

• Four

What is the calculated mass percent composition of carbon in CO2?

• 72.7%

• 50%

• 12.01%

• 27.29%

What is the calculated mass percent composition of oxygen in CO2?

• 72.7%

• 16.00%

• 27.29%

• 50%

What should the sum of the mass percent compositions of all elements in a compound equal?

• 50%

• 25%

• 100%

• 75%

If the mass percent of carbon in CO2 is 27.29%, what is the mass percent of oxygen?

• 16.00%

• 27.29%

• 50%

• 72.7%