Question

What is the percent of H2O in a sample of a hydrate whose mass is 1.1290 g if the mass of water in the sample was 0.1660 g?

Answer 1

The hydrate contains 14.70 % H₂O by mass.

Mass % H₂O = mass of water/mass of hydrate × 100 %

= 0.1660 g /1.1290 g × 100 % = 14.70 %