$X :\, 2SO_{2(g)} + O_{2(g)} $ $\rightleftharpoons$ $ 2SO_{3(g)}$
$Y:\, PCl_{5(g)} $ $\rightleftharpoons$ $ PCl_{3(g)} + Cl_{2(g)}$
$Z :\, 2HI_{(g)} $ $\rightleftharpoons$ $ H_{2(g)} + I_{2(g)}$
$X:2S{O_2} + {O_2} \rightleftharpoons 2S{O_3}$
$Y:PC{l_5} \rightleftharpoons PC{l_3} + C{l_2}$
$Z:2HI \rightleftharpoons {H_2} + {H_2}$
$2NH_3 + 5/2O_2 $ $\rightleftharpoons$ $ 2NO + 3H_2O, K_1, K_2$ અને $K_3$ ના સંદર્ભમાં ...... થાય.