The equilibrium constant at $298 \ K$ for a reaction $A + B \rightleftharpoons C + D$ is $100$. If the initial concentration of all the four species were $1 \ M$ each,then the equilibrium concentration of $D$ (in $mol \ L^{-1}$) will be:

The surface of copper gets tarnished by the formation of copper oxide. $N_2$ gas was passed to prevent the oxide formation during heating of copper at $1250 \ K$. However,the $N_2$ gas contains $1 \ \text{mole}\%$ of water vapour as impurity. The water vapour oxidises copper as per the reaction given below:
$2 Cu_{(s)} + H_2O_{(g)} \longrightarrow Cu_2O_{(s)} + H_{2(g)}$
$p_{H_2}$ is the minimum partial pressure of $H_2$ (in $\text{bar}$) needed to prevent the oxidation at $1250 \ K$. The value of $\ln(p_{H_2})$ is . . . . .
(Given: total pressure $= 1 \ \text{bar}$,$R = 8 \ J \ K^{-1} \ mol^{-1}$,$\ln(10) = 2.3$. $Cu_{(s)}$ and $Cu_2O_{(s)}$ are mutually immiscible.
At $1250 \ K$: $2 Cu_{(s)} + 1/2 O_{2(g)} \longrightarrow Cu_2O_{(s)}; \Delta G^\theta = -78,000 \ J \ mol^{-1}$
$H_{2(g)} + 1/2 O_{2(g)} \longrightarrow H_2O_{(g)}; \Delta G^\theta = -1,78,000 \ J \ mol^{-1}$)

Eight moles of a gas $AB_3$ attained equilibrium in a closed container of volume $1 \, dm^3$. The reaction is $2AB_{3(g)} \rightleftharpoons A_{2(g)} + 3B_{2(g)}$. If at equilibrium $2 \, moles$ of $A_2$ are present,then the equilibrium constant is ...... $mol^2 \, L^{-2}$.

Which one of the following statements is correct for a reversible reaction? $A$ catalyst

For the reactions $X \rightleftharpoons 2Y$ and $Z \rightleftharpoons P + Q$,the equilibrium constants $K_p$ and $K_q$ are in the ratio $1:9$. If the degree of dissociation of $X$ and $Z$ is the same,then the ratio of their total pressures is:

The reaction $2 NO_{2(g)} \rightleftharpoons N_2O_{4(g)}$ is at equilibrium in a closed $15 \ L$ vessel at $300 \ K$. The total weight of the mixture of $NO_2$ and $N_2O_4$ in the vessel is $64.4 \ g$. The equilibrium constant for the reaction is $K_p = 6.67$. Assuming ideal gas behavior,the total pressure in the vessel (in $atm$) is: [Given: Gas constant $R = 0.082 \ atm \ L \ K^{-1} \ mol^{-1}$]