Why is copper sulphate not stored in aluminium vessel?
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Aluminium is more reactive than copper. So the Aluminium will displace copper sulphate from its solution . After some days the blue colour of the solution will fade away, and copper (which has a reddish brown appearance) will be deposited on inner surface of aluminium vessel.In this way aluminium vessel will be destroy and the solution of copper sulfate will turn in aluminium sulfate.
2Al + 3CuSO4 → Al2(SO4)3 + 3Cu