Question

What do we observe when the crystals of copper nitrate are heated in a test tube?

Answer 1

Hint:We should know that after losing the moisture present in it the colour of the crystals gets changed and this must lead to the emission of the certain gas and results in some residue left.

Complete answer:
We must firstly discuss the copper nitrate crystals so copper nitrate crystals are inorganic compounds that form a blue crystalline solid. Further we must know that the anhydrous copper nitrate forms deep blue colour crystals and further they get sublime at a certain temperature and as we know that slime means to directly evaporate into the gaseous state from the solid state without getting converted to the liquid state. Further keeping the question in mind we must look at what happens to the crystals when they are heated . On little heating it loses the water molecule present but the interesting thing happens afterwards when the on heating more it gets decomposed and gives reddish brown gas and as we know the gas with such colour is none other than the nitrogen dioxide along with oxygen. As a result we found that the blue colour crystals get changed to the black residue. Also we must know that the copper nitrate has wide application as it is used as a catalyst in a number of processes as it easily gets converted into the copper oxide. It is also used to demonstrate the photovoltaic cells in schools basically.

Note:
We must note here that as we are continuously talking bout the crystals so you must wondering that there must be some shape of the crystals so the shape of the crystals is as follows that when the crystals are in anhydrous form then the possible shape is orthorhombic and if there are hydrates then the possible shape must be rhombohedral.