What is the effect of a decrease in pressure on each of the systems described by the

following reactions? Which way will each equilibrium shift when the pressure is

decreased?

a$.C_2{H}_{6(g)}{H}_{2(g)}+C_2{H}_{4(g)}$

b$.C{O}_{(g)}+\frac{1}{2}{O}_{2(g)}C{O}_{2(g)}+$ heat

c$.C{u}_{(aq)}^{2+}+4N{H}_{3(aq)}Cu(N{H}_3{)}_3^{2+}{?}_{(aq)}$

d$.PbS{O}_{4(s)}+H_{(aq)}^{+}P{b}_{(aq)}^{2+}+HS{O}_{4(aq)}^{-}$

e$.$

$A{g}_{(aq)}^{+}+C{l}_{(aq)}^{-}AgC{l}_{(s)}$