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32. Crude oil is separated into petroleum 35. The oxygen gas used in the contact process
products by use of fractional distillation. must be dust free to avoid poisoning the
vanadium (V) oxide catalyst. Which
Which fractions would be obtained between reaction would be affected if dust is
o
20 - 200 C and 275 - 375 C respectively? present?
o

20 - 200 C 275 - 375 C (A) S (g) + O (g) ☞ SO (g)
0
0
2
2
(B) 2S (g) + 3O (g) ☞ 2SO(g)

2
(A) Bitumen refinery gas (C) 2SO (g) + O (g) ☞ 2SO (g)
2
3
2
(B) Diesel kerosene (D) 2S (g) + 3O (g) + 2H O (l) ☞
(C) Naphtha refinery gas 2H SO (aq) 2 2
4
2
(D) Diesel gasoline
36. What is the purpose of green chemistry?
33. Purified N gas and H gas are reacted
2
2
together to form ammonia as shown below. (A) Removing wastes from industrial
reactions
N (g) + 3H (g) catalyst 2NH (g) (B) Designing chemical products that
3
2
2
∆H = –92 kJ mol¯ 1 maximize profits
(C) Inventing technologies that
Based on Le Chatelier’s principle, which will promote recycling of
combination of pressure and temperature productseration of hazardous
would give the highest yield of ammonia? substances
(D) Designing safer chemical products
(A) Low temperature, low pressure and processes that reduce or
(B) Low temperature, high pressure eliminate the use and gen
(C) High temperature, high pressure
(D) High temperature, low pressure 37. A polluted river near a paint factory is
tested with acidified potassium iodide and
a bright yellow precipitate is observed.
34. Ethanol formed by fermentation will Which of the following pollutants is likely
destroy the enzyme-producing yeast. What to be present?
is the lowest percentage of alcohol at
which this occurs? (A) PO 3-
(B) CN - 4
(A) 3 (C) Cr 3+
(B) 13 (D) Pb 2+
(C) 20
(D) 30

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02212010/SPEC/CAPE 2017