Concept:Le Chatelier's Principle identifies which specific stresses will cause a shift in the equilibrium position, heavily depending on the stoichiometry of the gases involved.
Formula:$$ \Delta n = \text{Moles}_{\text{products}} - \text{Moles}_{\text{reactants}} $$
Solution:- Calculate \( \Delta n \): Reactants = 2 moles. Products = 1 + 1 = 2 moles. \( \Delta n = 2 - 2 = 0 \).
- Because there is no change in the number of gaseous moles, changes in Pressure (3) or Volume (4) will have absolutely zero effect on the equilibrium position.
- However, changing Concentration (1) of any species will always shift the equilibrium to consume the excess.
- Changing Temperature (2) will also shift the equilibrium (forward in this case, as it is endothermic / +ive).
- Therefore, only factors 1 and 2 disturb this specific equilibrium.
Why other options are incorrect:Any option including 3 or 4 is incorrect because pressure/volume changes cannot stress a gaseous system where \( \Delta n = 0 \).
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