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 molar mass of the compound and multiplying by 100.

Front

How do you calculate the molar mass of a compound?

Back

To calculate the molar mass, sum the atomic masses of all the atoms in the compound's formula.

Front

What is the formula for calculating percent composition?

Back

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

Front

What is the percent composition of carbon in carbon monoxide (CO)?

Back

43%.

Front

What is the molar mass of CO2?

Back

44 g/mol.

Front

What is the percent composition of sulfur in MgSO4?

Back

27%.

Front

What is the percent composition of nitrogen in calcium nitrate (Ca(NO3)2)?

Back

17%.

Front

How do you find the percent composition of magnesium in Mg3(PO4)2?

Back

Calculate the molar mass of Mg3(PO4)2 and then use the formula for percent composition.

Front

What is the molar mass of magnesium (Mg)?

Back

24.31 g/mol.

Front

What is the molar mass of sulfur (S)?

Back

32.07 g/mol.