A student measured out a 5.790 g sample of a hydrated salt.After heating,the mass of an hydrous salt was found to be 3.701 g.Use these data to calculate the percent by mass of water in the hydrated...

A student measured out a 5.790 g sample of a hydrated salt.After heating,the mass of an hydrous salt was found to be 3.701 g.

Use these data to calculate the percent by mass of water in the hydrated salt

Expert Answers
jeew-m eNotes educator| Certified Educator

hydrated salts are salts which can absorb moisture. Once these hydrated salts are heated the water attached to salt will evaporate and the pure salt will remain.

Initial mass of the hydrated salt = 5.79g

    Final mass of the heated salt = 3.701g

 

Mass of water in the hydrated salt = 5.79-3.701

                                                 = 2.089g

 

Mass % of water in the hydrated salt = 2.089/3.701*100%

                                                     = 56.44%

 

So in the hydrated salt 56.44% of the mass is water.