Mole Concept Practice

Front

What is the mole concept?

Back

The mole concept is a method used in chemistry to quantify the amount of substance. One mole is defined as 6.022 x 10^23 particles (atoms, molecules, ions, etc.) of that substance.

Front

How do you calculate the number of moles from atoms?

Back

To calculate the number of moles from atoms, divide the number of atoms by Avogadro's number (6.022 x 10^23).

Front

What is Avogadro's number?

Back

Avogadro's number is 6.022 x 10^23, which is the number of particles in one mole of a substance.

Front

What is the molar mass of water (H2O)?

Back

The molar mass of water is approximately 18 g/mol.

Front

How many grams are in 2 moles of water?

Back

2 moles of water weigh 36 grams (2 moles x 18 g/mol).

Front

What is the empirical formula of a compound?

Back

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

Front

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

Back

To find the empirical formula, divide the subscripts in the molecular formula by their greatest common divisor.

Front

What is the relationship between moles and mass?

Back

Mass (grams) = Moles x Molar Mass (g/mol).

Front

How many moles are in 36 grams of water?

Back

There are 2 moles of water in 36 grams (36 g ÷ 18 g/mol).

Front

What is the molar mass of chlorine gas (Cl2)?

Back

The molar mass of chlorine gas (Cl2) is approximately 70.9 g/mol.