The ore that can be concentrated by using magnetic separation: (a) Corundum (b) Haematite (c) Calamine (d) Bauxite

A mineral from which a metal can be extracted economically is called: (a) Matrix (b) Ore (c) Flux (d) Alloy

Which of the following is not a constituent of the electrolytic mixture in the Hall-Heroult process? (a) Al₂O₃ (b) NaAlO₂ (c) Na₃AlF₆ (d) CaF₂

Copper, Zinc and Tin are the metals alloyed to form: (a) Duralumin (b) Brass (c) Bronze (d) Solder

In the electrolysis of molten aluminium oxide for extraction of aluminium, the following reactions take place: 1. 2. 3. 4. The reaction that takes place at the negative electrode is: (a) 1 (b) 2 (c) 3 (d) 4

The metal whose oxide can be reduced by common reducing agents: (a) Copper (b) Sodium (c) Aluminium (d) Potassium

Arrange the following as per the instruction given in the brackets: (a) Al, K, Mg, Ca (decreasing order of its reactivity) (b) N, Be, O, C (increasing order of non-metallic character) (c) P, Si, F, Be (decreasing order of valence electrons)

Write one use of the following alloys: (a) Bronze (b) Fuse metal

Identify the alloy in each case from the given composition: (a) Aluminium, magnesium, manganese, copper (b) Iron, nickel, chromium, carbon

The following sketch illustrates the process of conversion of Alumina to Aluminium: [5] Study the diagram and answer the following: (a) Name the constituent of the electrolyte mixture which has a divalent metal in it. (b) Name the powdered substance ‘X’ sprinkled on the surface of the electrolyte mixture. (c) What is the name of the process? (d) Write the reactions taking place at the electrodes ‘Y’ (anode) and ‘Z’ (cathode) respectively.

Complete the following sentences by choosing the correct answer from the brackets: (a) The salt that can be prepared by Direct Combination is ............... . [FeCl3 / FeCl2] (b) The metallic oxide which can be reduced by using common reducing agents is ............... . [Fe2O3 / Al2O3] (c) The metal nitrate which on thermal decomposition forms a black residue is ............... . [zinc nitrate / copper nitrate] (d) During the electrolysis of copper sulphate solution, if ............... is used as electrodes, the colour of the electrolyte does not fade. [copper / platinum] (e) The process of heating the concentrated ore in a limited supply or absence of air is ............... . [roasting / calcination]

Identify the gas evolved in each of the following reactions: (a) Methane undergoes complete combustion. (b) Copper carbonate is heated. (c) MnO2 reacts with concentrated HCl.