Distinguish by heating the following in dry test tube.

copper sulphate and copper carbonate

On heating copper sulphate, blue crystalline solid crumbles to form a white amorphous powder and gives off steamy vapours which condense on cooler parts of the test tube to form a colourless liquid (water).
On strong heating, a black solid is formed and a gas is evolved that turns moist blue litmus red and changes the colour of acidified K₂Cr₂O₇ solution from orange to green suggesting that it is SO₂.

On strongly heating copper carbonate, light green amorphous powder changes to black and a colourless odourless gas is evolved that extinguishes a burning wooden splinter and turns lime water milky but has no effect on acidified K₂Cr₂O₇ solution suggesting that it is CO₂.