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# The percentage of water of crystallization in ZnSO4.7H2O is [Zn = 65, S = 32, O ...

### Question

The percentage of water of crystallization in ZnSO4.7H2O is
[Zn = 65, S = 32, O = 1, H = 1]

A) 33%

B) 44%

C) 55%

D) 87%

### Explanation:

Molecular mass of ZnSO4.7H20
65 + 32 + 16 $$\times$$ 4 + 7(18) = 287
The mass of water of crystallisation = 126
$$\frac{126}{287} \times \frac{100}{1} = \frac{12600}{287}$$
= 44%

## Discussion (4)

• Molecular mass of ZnSO4.7H20
65 + 32 + 16 $$\times$$ 4 + 7(18) = 287
The mass of water of crystallisation = 126
$$\frac{126}{287} \times \frac{100}{1} = \frac{12600}{287}$$
= 44%

• Olanitee Akindayo

65 + 32 + 16 $$\times$$ 4 + 7(18) = 287
The mass of water of crystallisation = 126
$$\frac{126}{287} \times \frac{100}{1} = \frac{12600}{287}$$
= 44%

• Molecular mass of H20. *100%
----------------------------
Molecular mass of ZnSO4.7H20
7(2+16). *100
----------
(65+32+64)+7(2+16)
126. *100
-------
287
12600/287=43.90%~44%

• Molecular mass of ZnSO4.7H20
(65 + 32 + 64) + 7(2 + 16)
161 + 126 = 287g/mol
Percentage of water of crystallization
126*100/287 = 43.90~44%