Which of the following reactions will get affected by increasing the pressure?
Also, mention whether change will cause the reaction to go into forward or backward direction.
(i) $\mathrm{COCl}_{2}$ (g) $\longleftrightarrow \mathrm{CO}$ (g) $+\mathrm{Cl}_{2}$ (g)
(ii) $\mathrm{CH}_{4}(\mathrm{~g})+2 \mathrm{~S}_{2}(\mathrm{~g}) \longleftrightarrow \mathrm{CS}_{2}(\mathrm{~g})+2 \mathrm{H}_{2} \mathrm{~S}(\mathrm{~g})$
(iii) $\mathrm{CO}_{2}(\mathrm{~g})+\mathrm{C}(\mathrm{s}) \longleftrightarrow 2 \mathrm{CO}(\mathrm{g})$
(iv) $2 \mathrm{H}_{2}(\mathrm{~g})+\mathrm{CO}(\mathrm{g}) \longleftrightarrow \mathrm{CH}_{3} \mathrm{OH}(\mathrm{g})$
(v) $\mathrm{CaCO}_{3}$ (s) $\longleftrightarrow \mathrm{CaO}$ (s) $+\mathrm{CO}_{2}$ (g)
(vi) $4 \mathrm{NH}_{3}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \longleftrightarrow 4 \mathrm{NO}(\mathrm{g})+6 \mathrm{H}_{2} \mathrm{O}(\mathrm{g})$
The reactions given in (i), (iii), (iv), (v), and (vi) will get affected by increasing the pressure.
The reaction given in (iv) will proceed in the forward direction because the number of moles of gaseous reactants is more than that of gaseous products.
The reactions given in (i), (iii), (v), and (vi) will shift in the backward direction because the number of moles of gaseous reactants is less than that of gaseous products.