Formula Mass

Question

 

Calculate the formula mass of each compound given below. Keep at least one decimal place in atomic masses from the periodic table.

 

a) H2S2

 

b) HClO3

Answer 1

a) H2S2
2H = 2 x 1.01 = 2.02

2S = 2 x 32.07 = 64.14

2.02 + 64.14 = 66.16 = 66.2

b) HClO3

1H x 1.01 = 1.01

1Cl x 35.45 = 35.45

3O x 16.0 = 48.0

1.01 + 35.45 + 48.0 = 84.5