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Effect Temperature on the position of equilibrium

Answer Text:
(a). Effect Temperature on the position of equilibrium
Endothermic reactions:
- Increase in temperature favours the endothermic reactions;
Example:
#N_2O_4(g)overset(leftarrow)(rightarrow) 2NO_2(g); DeltaH= +ve#
pale yellow dark brown
- Increase in temperature shifts the equilibrium to the right; since the reaction is endothermic and hence more yield of nitrogen (IV) oxide; hence dark brown fumes will be observed;
- Decrease in temperature shifts the equilibrium to the left; since the reaction is endothermic favoured by low temperatures; hence formation of #N_2O_4#; and the pale yellow colour is observed;
-Exothermic reactions:
- Decrease in temperature favours exothermic reactions.
Example:
#2SO_2(g) + O_2(g) overset(leftarrow)(rightarrow) 2SO_3(g); DeltaH = -ve#
Thus:
- Decrease in temperature causes more yield of sulphur (VI) oxide; because the equilibrium shifts to the right; since the reaction is exothermic favoured by low temperatures;
- Increase in temperature causes #SO_3# to decompose decreasing its yields. Increase in temperature shifts the equilibrium to the left; because the reaction is exothermic which is favoured by low temperatures;