GCEChemistryChemical Equilibrium2020

For the reaction: $N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)$, $\Delta H = -92\,kJ\,mol^{-1}$. Which condition would shift the equilibrium to the right to produce more ammonia?

AIncreasing temperature and decreasing pressure
BDecreasing pressure and adding a catalyst
CIncreasing pressure and decreasing temperatureCORRECT
DDecreasing temperature and removing the catalyst
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Why the answer is C, and why the others tempt you.
The forward reaction is exothermic, so decreasing temperature favours the forward reaction by Le Chatelier's principle. The forward reaction also reduces the number of moles of gas from 4 to 2, so increasing pressure shifts equilibrium to the right where fewer gas moles exist. Together, high pressure and low temperature maximise ammonia yield.
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