Question

How many moles of hydrogen are in a
water sample that contains 80.0 milligrams of
oxygen?

Answer 1

H2O

A (O) = 16 g/mol

A (H) = 1.008 g/mol

n (O) = 0.08 /16 = 0.005 mol

n (H) = 2 x n (O) = 0.005 x 2 = 0.01 mol