Avogadro and Moles

Front

What is Avogadro's number?

Back

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

Front

How do you calculate the molar mass of a compound?

Back

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

Front

What is the molar mass of carbon dioxide (CO₂)?

Back

The molar mass of CO₂ is 44.01 g/mol (12.01 g/mol for C + 2 x 16.00 g/mol for O).

Front

What is the relationship between moles and mass?

Back

The mass of a substance in grams is equal to the number of moles multiplied by the molar mass (mass = moles x molar mass).

Front

What is the unit of molar mass?

Back

The unit of molar mass is grams per mole (g/mol).

Front

How many moles are in 36 grams of water (H₂O)?

Back

There are 2 moles of water in 36 grams (molar mass of H₂O is 18 g/mol).

Front

What does one mole of a substance represent?

Back

One mole of a substance represents 6.022 x 10^23 particles of that substance.

Front

Why do chemists use the mole as a unit?

Back

Chemists use the mole to simplify the counting of large numbers of small particles, making calculations easier.

Front

What is the molar mass of sodium chloride (NaCl)?

Back

The molar mass of NaCl is 58.44 g/mol (22.99 g/mol for Na + 35.45 g/mol for Cl).

Front

How do you convert grams to moles?

Back

To convert grams to moles, divide the mass of the substance by its molar mass (moles = grams / molar mass).