Pawan is a student of class IX. The students of his class have recently studied the topic on the separation of various types of mixtures. One day, when the students were performing experiements in the science laboratory, their chemistry teacher Mr. Jain came to the laboratory with a packet in this hand. Mr. Jain told Pawan that the packet contained a mixture of aluminium powder, sulphur powder and nuckel powder. He asked Pawan to separate all the three constituents of this mixtures. Mr. Jain allowed the use of any other equipment/device/chemical, etc., required for this purpose from the laboratory. Pawan thought over the methods to be used for separating the given mixture for a while and then started working on the separation of mixture. He succeeded all the constituents of the mixture, one by one. Mr. Jain appreciated his effort.
(a) Which property of sulphur powder could be used by Pawan to separate it from aluminium powder and nickel powder ?
(b) Describe briefly, how Pawan separated sulphur powder from the mixture of aluminium powder, sulphur powder and nickel powder
(c) Which property of nickel powder could be used by Pawan to separate it from aluminium powder ?
(d) Describe briefly, how Pawan separated nickel powder from aluminium powder.
(e) What values are displayed by Pawan in this episode ?

Explanation

(a) Sulphur is soluble in an organic liquid 'carbon disulphide' (where aluminium powder and nickel powder are not solution in carbon disulphide). So, the property of solubility of sulphur powder in carbon disulphide is used to separate it from aluminium powder and nickel powder
(b) The mixture of aluminium powder, sulphur powder and nickel powder is taken in a test-tube and shaken with some carbon disulphide. Sulphur powder present in the mixture dissolves in carbon disulphide. On filtering, aluminium powder and nickel powder remain behind on the filter paper as residue and sulphur dissolved in carbon disulphide is obtained as a filtrate. On evaporating the filtrate, carbon disulphide is eliminated and sulphur powder is left behind
(c) Nickel is a magnetic material which is attracted by a magnet (whereas aluminium is a non-magnetic material which is not attracted by a magnet). So, the magnetic property of nickel is used to separate nickel powder from aluminium powder
(d) The mixture containing aluminium powder is taken in a watch glass. A horse-shoe type magnet is moved in the mixture of aluminium powder and nickel powder repeatedly. The nickel powder is attracted by the magnet, it clings to the poles of the magnet and gets separated. Aluminium powder is not attracted by the magnet. So, aluminium powder remains behind
(e) The various values displayed by Pawn in this episode are (i) Knowledge of the solubility of sulphur in carbon disulphide , magnetic nature of nickel and non-magnetic nature of aluminium, and (ii) Application of knowledge in solving real-life problems.