$\Delta _f G^o$ at $500 \, K$ for substance '$S$' in liquid state and gaseous state are $+100.7 \, kcal \, mol^{-1}$ and $+103 \, kcal \, mol^{-1}$,respectively. The vapour pressure of liquid '$S$' at $500 \, K$ is approximately equal to $(R = 2 \, cal \, K^{-1} \, mol^{-1}) \dots \dots \text{atm}$.

The value of $K_{c} = 4.24$ at $800 \, K$ for the reaction,
$CO_{(g)} + H_{2}O_{(g)} \rightleftharpoons CO_{2(g)} + H_{2(g)}$
Calculate equilibrium concentrations of $CO_{2}$,$H_{2}$,$CO$ and $H_{2}O$ at $800 \, K$,if only $CO$ and $H_{2}O$ are present initially at concentrations of $0.10 \, M$ each.

At $T$ $(K)$,the equilibrium constant for the reaction $H_{2(g)} + Br_{2(g)} \rightleftharpoons 2 HBr_{(g)}$ is $1.6 \times 10^5$. If $10 \ bar$ of $HBr$ is introduced into a sealed vessel at $T$ $(K)$,the equilibrium pressure of $HBr$ (in $bar$) is approximately

In which of the following equilibria is $K_{eq} > 1$?

Consider the reaction,$P(aq) \rightleftharpoons Q(aq)$ with an equilibrium constant $K=1.5$. The reaction is started in a vessel with a concentration of $[P]$ of $2 \ M$ and concentration of $[Q]=0$. When the equilibrium is established,half the amount of $P$ is removed,and the reaction is allowed to re-equilibrate. The concentration of $Q$ in the vessel (in $M$) is closest to

At $473 \ K$, equilibrium constant $K_{c}$ for decomposition of phosphorus pentachloride, $PCl_{5}$, is $8.3 \times 10^{-3}$. If decomposition is depicted as,
$PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}, \Delta_{r}H^{\Theta} = 124.0 \ kJ \ mol^{-1}$
$(a)$ Write an expression for $K_{c}$ for the reaction.
$(b)$ What is the value of $K_{c}$ for the reverse reaction at the same temperature?
$(c)$ What would be the effect on $K_{c}$ if $(i)$ more $PCl_{5}$ is added $(ii)$ pressure is increased $(iii)$ the temperature is increased?