A child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in figure. The filter paper was removed when the water moved near the top of the filter paper.

(i) Identify the technique used by the child.

(ii) What would you expect to see, if the ink contains three different coloured components?
(a) We will not see any band on the filter paper.
(b) We would see three bands on the filter paper at various lengths.
(c) We would see infinite bands on the filter paper.
(d) We would see single band on the filter paper.
iii) Give one application where you can use this technique.
(a) To separate salt from sand
(b) To separate wheat from husk
(c) To separate oil from water
(d) To separate drugs from blood.
(iv) For the separation of what kind of substances is the above process used ?
(a) For the separation of insoluble substances
(b) For the separation of single solute that dissolves in single solvent.
(c) For the separation of those solutes that dissolve in the same solvent.
(d) For the separation of those solutes that dissolve in the different solvents.
(v) What is chromatography ?
(a) It is an agricultural method to separate grains
(b) A method to separate magnetic impurities from non-magnetic impurities
(c) The process of separating the suspended particles of an insoluble substance
(d) Method of separating and identifying various components in a mixture, which are present in small trace quantities.

A Chemistry teacher explained the different types of separation of mixtures with the help of given adjoined chart. Now, in a practical test, students were provided with give samples and they were asked to separate the samples applying suitable separation methods. Now the students have to select the correct methods of separation.
(i) Fine mud particles suspended in water.

(ii) Oil from water.

(iii) Sodium chloride from its solution in water.

(iv) Camphor from salt.

(v) Cream from milk

In the given below activity, on heating the solution, water evaporates, and we get back the ink dye in the watch glass. The different substance has a different boiling point. We use this property to separate the components of the mixture. Here, the boiling point of ink is much higher than that of water. On heating the ink solution, water evaporates while ink dye remains in the china dish.

(i) Name the process shown in the diagram.

(ii) Which type of substance can be separated by this method ?
(a) Any solvent from its non-volatile solute.
(b) The volatile solvent from its non-volatile solute.
(c) The non-volatile solvent from its non-volatile solute.
(d) The volatile solvent from its volatile solute.
(iii) What can we interpret about the nature of ink ?

(iv) Name the component which gets evaporated.
(a) Heating leads to the evaporation of water.
(b) Heating leads to the evaporation of dyes.
(c) Heating leads to the filtration of water.
(d) Heating leads to the distillation of dyes.
(v) Define the process shown in the diagram
(a) It is the process of conversion of a liquid into its vapours.
(b) It is a process of separating insoluble component by filtering the solution
(c) It is a process that separates a pure solid in the form of its crystals
(d) It is a technique to separate two miscible liquids

We take some ammonium chloride in a china dish and place the china dish on a tripod stand (see Figure). The china dish is covered with an inverted glass funnel. A loose cotton plug is put in the upper, open end of the funnel to prevent the ammonium chloride vapours from escaping into the atmosphere. The china dish is heated by using a burner. On heating, ammonium chloride changes into white vapours. These vapours rise up and get converted into solid ammonium chloride on coming in contact with the cold, inner walls of the funnel (see Figure). In this way, ammonium chloride collects on the inner sides of the funnel in the form of a sublimate and can be removed.

(i) What name is given to the phenomenon which takes place?

(ii) One of the following does not undergo sublimation. This one is :

(iii) The conversion of a solid into vapours without passing through the liquid state is called : 

(iv) When heat is constantly supplied by a burner to boiling water, then the temperature of water during vaporisation :

(v) During summer days, water kept in an earthen pot (pitcher) becomes cool because of the phenomenon of :