Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles.
12 g CuBr2 ( 1 mol / 223.37 g) ( 6.022 x 10^23 molecules / mole ) = 3.24x10^22 molecules CuBr2