Solution:
SOLUTION
Molecular weight of CuSO4.5H2O = 249.5gmol−1
The reaction for liberation of I2;
2CuSO4.5H2O + KI = I2 + Cu2I2 + 2K2SO4 + 5H2O
2.54g of I2 = 2.54 /254 = 0.01 moles of I2
Now, 1 mole of I2 is liberated from 2 moles of CuSO4.5H2O
∴0.01 mole of I2 will be liberated from 2×0.01 mole i.e. 0.02 mole of CuSO4.5H2O.
∴ Amount of CuSO4.5H2O=0.02 mole × 249.5gmol−1=4.99gm