ANAL0387: Percent Water in a Hydrate

3. The mass of a crucible and a hydrated salt was found to be 21.447 g. The mass of the crucible and the

anhydrous salt was 20.070 g. The mass of the crucible was 17.985 g.

(1) Calculate the mass of the hydrate heated.

Mass of the hydrate heated = 3.462 g

Solution and Explanation: A hydrate is a salt or a compound that contains water of crystallization. For example, hydrated sodium carbonate which contains 10 moles of water of crystallization, Na₂CO₃.10H₂O. In our case we are required to determine the mass of the hydrate; Mass of the hydrate heated

Mass of the hydrate = mass of crucible and hydrate salt - mass of the crucible

Mass of crucible and hydrates salt = 21.447 g

Mass of the crucible = 17.985 g

Therefore;

Mass of the hydrate = 21.447 g - 17.985 g

= 3.462 g