A student performed the Separation by Fractional Crystallization experiment described with the following results:
Initial mass of sample mixture: 4.958g, mass of salicylic acid recovered, 0.586g; mass of CuSO4•5H2O recovered, 3.12g.
The recovered CuSO4•5H2O was then heated for 20 minutes at 120°C. The mass of the new hydrate was 2.17g.
(The molar mass of H2O = 18.015 g/mol, and the molar mass of CuSO4= 159.61g/mol)
Calculate the mass of CuSO4 in the new hydrate (CuSO4•XH2O).