Calculate the number of atoms in a 27.2 mg sample of Ga.

Question

The molar mass of Gallium (Ga) is 69.72 g/mol

Answer 1

27.2 mg of Ga needs to be converted to grams:

27.2 mg x (1g/1000mg) = 0.0272 g Ga

Grams of Ga need to be converted to moles using the molar mass (69.72 g/mol):

0.0272 g Ga x (1 mole Ga/69.72 g Ga) = 0.00039 mole Ga

Moles of Ga need to be converted to atoms:

0.00039 mole Ga x (6.02 x 10^23 atoms/1 mol Ga) = 2.35x10^20 atoms of Ga