Calculating Formula Mass and Moles

Front

What is the gram-formula mass of a compound?

Back

The gram-formula mass is the sum of the atomic masses of all the atoms in a formula unit of the compound, expressed in grams.

Front

How many grams are in 1 mole of a substance?

Back

1 mole of a substance contains a mass equal to its gram-formula mass.

Front

Calculate the mass of 1.5 moles of CO2 (gram-formula mass = 44 g/mol).

Back

66 g

Front

Calculate the mass of 2.0 moles of NO2 (gram-formula mass = 46 g/mol).

Back

92 g

Front

What is the formula to calculate the number of moles?

Back

Number of moles = mass (g) / gram-formula mass (g/mol).

Front

How many moles are in a 78.8-gram sample of MgCO3 (gram-formula mass = 84.3 g/mol)?

Back

0.935 mol

Front

What is the relationship between moles and mass?

Back

The mass of a substance is directly proportional to the number of moles, based on the formula: mass = moles × gram-formula mass.

Front

What is the formula mass of a compound?

Back

The formula mass is the sum of the atomic masses of its constituent atoms.

Front

If a compound has a gram-formula mass of 48 g, what is the mass of 1 mole of this compound?

Back

48 g

Front

What is the mass of 0.5 moles of H2O (gram-formula mass = 18 g/mol)?

Back

9 g