chemistry molarity

Question

Below are sample experimental data for this week's lab.

Mass of the Test Tube	4.458
Mass of Test Tube and Unknown Hydrate:	9.641
Mass of Test Tube and Anhydrous Salt:	7.310

Determine the % water in the unknown salt. 

Answer 1

Let's call the lines of data a, b, and c

Mass of the salt hydrate is b-a

Mass of the water is b - c

percent water is the mass of water/mass of salt hydrate x 100

Please consider a tutor. Take care.