Answer
a. 70.90 g/mol
b. 90.08 g/mol
c. 262.9 g/mol
d. 83.98 g/mol
Work Step by Step
1. Consult a periodic table in order to get the atomic mass of each element, and then multiply it by its subscript.
2. Sum the masses of each element in the compound.
a. ( 35.45 $\times$ 2 )= 70.90 g/mol
b. ( 1.008 $\times$ 6 )+ ( 12.01 $\times$ 3 )+ ( 16.00 $\times$ 3 )= 90.08 g/mol
c. ( 24.31 $\times$ 3 )+ ( 16.00 $\times$ 8 )+ ( 30.974 $\times$ 2 )= 262.9 g/mol
d. ( 26.98 $\times$ 1 )+ ( 19.00 $\times$ 3 )= 83.98 g/mol