3. The manufacture of sulphuric acid is based on the equilibrium reaction
| SO2(g) + 02(g) --> 2SO3(g) | /\H = -197 kJ mol-1 |
(a) The equilibrium is a dynamic equilibrium; explain the nature of such an equilibrium.
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(b) State and explain the effects of the
following on the equilibrium position:
(i) an increase in temperature;
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(ii) the presence of a catalyst.
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(c) State and explain the effects of the
following on the rate of attainment of equilibrium:
(i) an increase in temperature;
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(ii) the presence of a catalyst.
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(d) Although the reaction is exothermic in the forward direction there is no appreciable reaction between sulphur dioxide and oxygen at room temperature. Use this reaction to explain the ideas of thermodynamic and kinetic stability.
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Although the reaction is an equilibrium reaction, industrially this and other similar reactions do not usually achieve equilibrium. Suggest why this is so.
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Total 14 marks