At $25\,^oC$,the equilibrium $SO_2Cl_2(g) \rightleftharpoons SO_2(g) + Cl_2(g)$ is established in a closed vessel. When $Cl_2$ is added to the equilibrium mixture,which of the following statements is/are correct for the system?
$(1)$ Change in concentrations of $SO_2$,$Cl_2$,and $SO_2Cl_2$.
$(2)$ More $Cl_2$ is produced.
$(3)$ The concentration of $SO_2$ decreases and the concentration of $SO_2Cl_2$ increases.

When $NaNO_{3(s)}$ is heated in a closed vessel,$O_{2(g)}$ is released and $NaNO_{2(s)}$ remains. The equilibrium is: $NaNO_{3(s)} \rightleftharpoons NaNO_{2(s)} + 1/2 O_{2(g)}$. Which of the following is correct?

Which of the following reactions will be affected by increasing the pressure? Also,mention whether the change will cause the reaction to proceed in the forward or backward direction.
$(i)$ $CaCl_{2(s)} \rightleftharpoons CO_{(g)} + Cl_{2(g)}$
$(ii)$ $CH_{4(g)} + 2S_{2(g)} \rightleftharpoons CS_{2(g)} + 2H_{2}S_{(g)}$
$(iii)$ $CO_{2(g)} \rightleftharpoons C_{(s)} + 2CO_{(g)}$
$(iv)$ $2H_{2(g)} + CO_{(g)} \rightleftharpoons CH_{3}OH_{(g)}$
$(v)$ $CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$
$(vi)$ $4NH_{3(g)} + 5O_{2(g)} \rightleftharpoons 4NO_{(g)} + 6H_{2}O_{(g)}$

Does the number of moles of reaction products increase,decrease,or remain the same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?
$(a)$ $PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}$
$(b)$ $CaO_{(s)} + CO_{2(g)} \rightleftharpoons CaCO_{3(s)}$
$(c)$ $3Fe_{(s)} + 4H_{2}O_{(g)} \rightleftharpoons Fe_{3}O_{4(s)} + 4H_{2(g)}$

Some inert gas is added at constant volume to the following reaction at equilibrium:
$NH_4HS_{(s)} \rightleftharpoons NH_{3(g)} + H_2S_{(g)}$
Predict the effect of adding the inert gas.

In the following reversible reaction $2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g) + Q \ \text{cal}$. The most suitable condition for the higher production of $SO_3$ is: