Question

Name the metal which can be purified by distillation process.

Answer 1

Hint: Distillation is used to purify metals with low boiling points. We use the difference in boiling points of impurities and metal as a basis for this process to actually work. Let us understand how distillation works.

Complete answer:
-Distillation is a method of heating impure liquid to its boiling point and cooling the vapours to get the pure liquid.
-As mentioned in the hint, metals with low boiling point are purified using this method. So metals like Zinc, Cadmium, Mercury are used in this process.
-In this method, the impure metal is heated in distilling flask and after some time the metal will start boiling and get converted into its vapours. The impurities will not get converted into vapours due to their high boiling point and is still in its liquid form in the distilling flask.
-The vapours will then pass through the condenser where in the heat exchange happens causing the temperature of the vapours to decrease and converting them again back into liquid. This liquid metal is called the distillate and gets collected in the receiving flask. Thus, separation is achieved.
-The liquid metal now can be further solidified to get solid metal.

Note:
There are other purification techniques also like liquation, Electrolysis, Zone refining etc. which can be used to get pure metal from its impure form. The boiling points of zinc, cadmium and mercury are \[{{907}^{\circ }},{{765}^{\circ }},{{356}^{\circ }}\] respectively.