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Effect of temperature on the rate of reaction

Answer Text:
(b). Effect of temperature.
- An increase in temperature increases the rate of a chemical reaction.
Reasons:
- Increase in temperature increases the kinetic energy of the reacting particles;
- The particles therefore move faster leading to more frequent and more effect collisions.
- The rate of reaction therefore increases;
Example: reaction between sodium thiosulphate and dilute HCl(aq) Stoichiometric equation:
`Na_2S_2O_3(aq)+2HCl(aq) to 2NaCl(aq) + H_2O (l)+S(s) +SO_2(g)`
ionic equation:
`S_2O_3^(2-)+2H^(+) to S(s) +SO_2(g) + H_2O(l)`
- The time taken to precipitate the same amount of sulphur by the same volume of acid at different temperatures is measured.
- Concentration of thiosulphate solution and the acid are kept constant.

- The rate is proportionate to `1/ t`; Hence;
- The higher the temperature the shorter the time for completion of the reaction and the higher the rate of the reaction;
-Alternatively: You can plot a graph of `1/ t` against temperature;