Given the following equilibria:
$N_2 + 3H_2 \rightleftharpoons 2NH_3 : K_1$
$N_2 + O_2 \rightleftharpoons 2NO : K_2$
$H_2 + 1/2O_2 \rightleftharpoons H_2O : K_3$
Then the equilibrium constant for the reaction $2NH_3 + 5/2O_2 \rightleftharpoons 2NO + 3H_2O$ in terms of $K_1, K_2,$ and $K_3$ will be:

Consider the following chemical equilibrium of the gas phase reaction at a constant temperature: $A_{(g)} \rightleftharpoons B_{(g)} + C_{(g)}$. If $p$ is the total pressure,$K_p$ is the equilibrium constant,and $\alpha$ is the degree of dissociation,then which of the following is true at equilibrium?

Which of the following equations is incorrect?

At $473 \ K$,the equilibrium constant $K_{c}$ for the decomposition of phosphorus pentachloride is $8.3 \times 10^{-3}$. If the decomposition is depicted as:
$PCl_{5(g)} \longleftrightarrow PCl_{3(g)} + Cl_{2(g)} \quad \Delta_{r}H^{\circ} = 124.0 \ kJ \ mol^{-1}$
$(a)$ 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?

For the reaction,$2SO_{2(g)} + O_{2(g)} \to 2SO_{3(g)}$
$\Delta H = -57.2 \ kJ \ mol^{-1}$ and $K_C = 1.7 \times 10^{16}$
Which of the following statement is $INCORRECT$?

Consider a reaction that is first order in both directions: $A \underset{K_b}{\stackrel{K_f}{\rightleftharpoons}} B$. Initially only $A$ is present,and its concentration is $A_{0}$. Assume $A_{t}$ and $A_{\text{eq}}$ are the concentrations of $A$ at time $t$ and at equilibrium,respectively. The time $t$ at which $A_{t} = (A_{0} + A_{\text{eq}})/2$ is $....$