Percent Composition

Front

What is percent composition?

Back

Percent composition is the percentage by mass of each element in a compound, calculated by dividing the mass of the element by the total mass of the compound and multiplying by 100.

Front

How do you calculate the percent by mass of an element in a compound?

Back

Percent by mass = (mass of element in 1 mole of compound / molar mass of compound) x 100.

Front

What is the percent by mass of fluorine in CaF2? (Molar mass = 78 g/mol)

Back

49%.

Front

What is the percent composition of Benzene, C6H6?

Back

C = 92.2%, H = 7.8%.

Front

What is the percent by mass of sodium in NaCl?

Back

39%.

Front

What is the percent by mass of oxygen in MgO?

Back

40%.

Front

Which element in KCN has a percent composition of 60.0%?

Back

K.

Front

What is the molar mass of Carbon (C)?

Back

12.01 g/mol.

Front

What is the molar mass of Hydrogen (H)?

Back

1.008 g/mol.

Front

What is the molar mass of Oxygen (O)?

Back

16.00 g/mol.