Calculate the number of caco3 molecules containing 500 g of chalk.

Chalk consists mainly of calcium carbonate with a small amount of impurities that will not be considered in this task.

Knowing the mass of chalk, we can calculate the amount of moles of calcium carbonate. Multiplying the number of moles by the Avogadro number of Na, we obtain the number of calcium carbonate molecules in 500 g of chalk. Avogadro’s number shows how many particles (atoms, molecules, etc.) are contained in 1 mole of a substance.

Na = 6.02 * 10 ^ 23

M (CaCO3) = 40 + 12 + 16 * 3 = 100 g / mol

n (CaCO3) = m / M = 500/100 = 5 mol

N = n * Na = 5 * 6.02 * 10 ^ 23 = 3.01 * 10 ^ 24 molecules