Question

In the reaction, $2S{O}_2\left(g\right)+O_2\left(g\right)\rightleftharpoons 2S{O}_3\left(g\right)+X\text{cal}$, most favourable conditions of temperature and pressure for greater yield of $S{O}_3$ are:

• A. Low temperature and low pressure
• B. High temperature and low pressure
• C. High temperature and high pressure
• D. Low temperature and high pressure

Answer 1

The correct option is D Low temperature and high pressure

The given reaction is exothermic as $Xcal$ amount of heat is released during the reaction.
For an exothermic reaction, on decreasing the temperature equilibrium will shift in forward direction. Hence, low temperature will be favoured for formation of $S{O}_3$.
According to the Le Chatelier's principle, on increasing pressure, equilibrium will shift in the direction where lesser number of gaseous moles are present. Hence, on increasing pressure equilibrium will shift in forward direction for the given system. Hence, high pressure is favourable for greater yield of $S{O}_3$.