(b) What volume of nitric oxide, NO, measured under standard conditions, 



can be obtained by adding 10.0 grams of copper to excess of dilute 

 nitric acid according to the equation : 



3CU+8HNO3 =3Cu(N03)2+4H20+2NO ? 



(Atomic weights: Cu 64, O 16, N 14, H 1. One liter of nitric oxide at 0° C. 

 and 760 mm. weighs 1 .34 grams.) 



Part II 

 (Omit one group. Each question counts 10.) 



Group A 



6. Answer five parts of this question. How could you demonstrate experi- 



mentally that: {a) Nitric acid is an oxidizing agent ? {b) Sulphur dioxide 

 is a reducing agent ? (c) Copper sulphate is a salt ? {d) Alcohol contains 

 carbon? (e) Kerosene is a mixture? (/) Litharge contains lead? 



7. How could you make: (a) Zinc sulphate from zinc chloride? {b) Copper 



from copper sulphate ? [c) Ferric oxide from ferric chloride ? {d) Sodium 

 sulphite solution from sulphur ? 



Group B 



8. {a) What is meant by the term "reversible reaction"? 



ib) Under what three conditions will a reaction proceed to completion ? 



(c) Illustrate each of these conditions separately by writing the equation 



of a suitable reaction, showing which condition is fulfilled in each case. 



9. (a) State Gay-Lussac's law of combining volumes. What volume of oxygen 



is required for the complete combustion of five liters of acetylene, 

 C2H2? All measurements are to be made under the same conditions 

 of temperature and pressure. 

 (6) One liter of gas A weighs 1 . 98 grams. One liter of gas B weighs . 77 

 gram, under the same conditions. The molecular weight of A is 44. 

 What is the molecular weight of B ? 



Group C 



10. (a) Describe the electrolytic process for silver plating. 



{b) Of what chemical elements are ordinary fuels composed? What pro- 

 ducts are formed by their combustion ? Aside from expense, what are 

 the disadvantages of sulphur as a fuel ? 



11. (a) Show briefly the relation of four constituents of the atmosphere to the 



vital processes of plants and of animals. 

 {b) Describe the chemical changes that occur in a blast-furnace for making 

 pig-iron from an ore consisting of ferric oxide and sand. 



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