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Preparations and Uses of Sodium Carbonate

When copper s...

Question

When copper sulphate crystals are heated in a test tube, we observe :

A

a colourless gas with no smell is evolved.

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B

blue colour of the salt fades & no gas is evolved

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C

blue colour of the salt fades & green gas is evolved

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D

a brown gas is evolved.

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Solution

The correct option is B a colourless gas with no smell is evolved.
The colour of hydrated copper sulphate $C u S O_{4} .5 H_{2} O$ is blue that turns into white, when heated at high temperature in a test tube, due to the loss of water molecules from copper sulphate.

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Q. You are given the following materials:
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Preparations and Uses of Sodium Carbonate

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