$A$ vapor at atmospheric pressure is gradually heated from $25\,^oC$. Initially,its color deepens,but above $160\,^oC$,the color fades. At $600\,^oC$,the vapor becomes almost colorless. However,increasing the pressure at this temperature makes the color deep again. What is this vapor?

In the reaction ${A_2}_{(g)} + 4{B_2}_{(g)} \rightleftharpoons 2A{B_4}_{(g)}$ where $\Delta H < 0$,the formation of $AB_{4(g)}$ will be favoured by:

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.
$(i)$ $CaCl_{2(s)} \rightleftharpoons CO_{(g)} + Cl_{2(g)}$
$(ii)$ $CH_{4(g)} + 2S_{2(g)} \rightleftharpoons CS_{2(g)} + 2H_{2}S_{(g)}$
$(iii)$ $CO_{2(g)} \rightleftharpoons C_{(s)} + 2CO_{(g)}$
$(iv)$ $2H_{2(g)} + CO_{(g)} \rightleftharpoons CH_{3}OH_{(g)}$
$(v)$ $CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$
$(vi)$ $4NH_{3(g)} + 5O_{2(g)} \rightleftharpoons 4NO_{(g)} + 6H_{2}O_{(g)}$

The reaction $SO_2 + Cl_2 \rightleftharpoons SO_2Cl_2$ is exothermic. If some $SO_2$ is added to the equilibrium mixture at constant volume,then ...........

The reaction $3O_2 \rightleftharpoons 2O_3; \Delta H = 69 \ kcal$ is favoured by..........

For the reaction $PCl_{3(g)} + Cl_{2(g)} \rightleftharpoons PCl_{5(g)}$,the position of equilibrium can be shifted to the right by