The mass percentage of water of crystallisation in CuSO4.5H2O is (Cu = 63.5, S = 32, O = 16, H = 1):

NEET levelSingle correct optionDifficulty 1 of 3mc022

The mass percentage of water of crystallisation in $CuSO X_{4} \cdot 5 H X_{2} O$ is (Cu = 63.5, S = 32, O = 16, H = 1):

M = 63.5 + 32 + 64 + 5 (18) = 249.5

. Water

= 90

. Percentage of water

= 90/249.5 \times 100 = 36.07%

. The

100 - p

option is the anhydrous salt; dividing by

159.5

ignores the water in the total.

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