Consider the reaction :
`2SO_2(g)+O_2(g) hArr 2SO_3(g)` +189.4 kJ .
Indicate the direction in which the equilibrium will shift when
(i)temperature is increased
(ii) volume is increased
(iii) a catalyst is added
(iv) pressure is decreased
(v) concentration of `SO_2` is increased
(vi) helium gas is added at constant volume so that the total pressure is increased
(vii) helium gas is added at constant pressure.

Explanation

To determine the direction in which the equilibrium will shift for the reaction

\[ 2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g) + 189.4 \text{ kJ} \]

under various conditions, we can apply Le Chatelier's principle. This principle states that if an external change is applied to a system at equilibrium, the system will adjust to counteract that change and restore a new equilibrium.

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