Mole Conversions Test Review 2024

Front

What is Avogadro's number?

Back

Avogadro's number is 6.02 x 10^23, which is the number of molecules in one mole of a substance.

Front

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

Back

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

Front

What is the empirical formula?

Back

The empirical formula is the simplest whole-number ratio of atoms of each element in a compound.

Front

How do you determine the empirical formula from a molecular formula?

Back

Divide the subscripts in the molecular formula by their greatest common divisor.

Front

What is the molar mass of a compound?

Back

The molar mass is the mass of one mole of a substance, usually expressed in grams per mole (g/mol).

Front

How do you convert grams to moles?

Back

Moles = mass (g) / molar mass (g/mol).

Front

What is the relationship between moles and molecules?

Back

1 mole of any substance contains Avogadro's number (6.02 x 10^23) of molecules.

Front

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

Back

The percent composition of oxygen in water is approximately 88.8%.

Front

How do you find the molecular formula from the empirical formula?

Back

Multiply the subscripts in the empirical formula by a whole number to match the molar mass of the compound.

Front

What is the significance of the empirical formula in chemistry?

Back

The empirical formula provides the simplest ratio of elements in a compound, which is useful for understanding its composition.