For the reaction,$0.5 C_{(s)} + 0.5 CO_{2(g)} \rightleftharpoons CO_{(g)}$,the equilibrium pressure is $12 \ atm$. If $CO_2$ conversion is $50 \%$,the value of $K_p$,in $atm$,is:

Calculate:
$(a)$ $\Delta G^{\circ}$ and
$(b)$ the equilibrium constant for the formation of $NO_2$ from $NO$ and $O_2$ at $298 \, K$
$NO_{(g)} + 1/2 O_{2(g)} \longleftrightarrow NO_{2(g)}$
Given:
$\Delta G^{\circ}_f(NO_2) = 52.0 \, kJ/mol$
$\Delta G^{\circ}_f(NO) = 87.0 \, kJ/mol$
$\Delta G^{\circ}_f(O_2) = 0 \, kJ/mol$

$5 \ moles$ of $SO_2$ and $5 \ moles$ of $O_2$ are allowed to react. At equilibrium,it was found that $60\%$ of $SO_2$ is used up. If the partial pressure of the equilibrium mixture is $1 \ atm$,the partial pressure of $O_2$ is (in $atm$)

$2NOBr(g) \rightleftharpoons 2NO(g) + Br_2(g)$. If nitrosyl bromide $(NOBr)$ is $40\%$ dissociated at a certain temperature and a total pressure of $0.3 \ atm$,what is the $K_P$ for the reaction $2NO(g) + Br_2(g) \rightleftharpoons 2NOBr(g)$?

The following reaction is performed at $298 \, K$.
$2 NO_{(g)} + O_{2(g)} \rightleftharpoons 2 NO_{2(g)}$
The standard free energy of formation of $NO_{(g)}$ is $86.6 \, kJ/mol$ at $298 \, K$. What is the standard free energy of formation of $NO_{2(g)}$ at $298 \, K$? $(K_p = 1.6 \times 10^{12})$

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?