Question

a sample of magnesium consists of 1.92 *10^22 magnesium atoms what is the mass of the sample in grams​

Answer 1

1 mole of Mg = 24g = 6.02 x 10^23 atoms

mass of 1 atom = 24/6.02 x 10^23 = 4 x 10^-23g

Mass of 1.92 x 10^22 atoms = 4 x 1.92 x 10^-23 x 10^22 = 7.68 x 10^-1 = 0.768g