For the reaction $N_{2(g)} + 3H_{2(g)} \rightleftharpoons 2NH_{3(g)} + \text{heat}$,which of the following relations is correct?

For the reaction $PCl_5 \rightleftharpoons PCl_3 + Cl_2$,at equilibrium,the number of moles of $PCl_5$,$PCl_3$,and $Cl_2$ are $2 \ mol$ each,and the total pressure is $3 \ atm$. What is the value of $K_p$ in $atm$?

For the reaction $CO_{(g)} + 2H_{2(g)} \rightleftharpoons CH_3OH_{(g)}$,the true condition is:

For which of the following reactions will the value of $\Delta n = \sum n_p - \sum n_r$ be positive? $(1)$ $C_2H_{6(g)} \rightleftharpoons C_2H_{4(g)} + H_{2(g)}$ $(2)$ $N_{2(g)} + O_{2(g)} \rightleftharpoons 2NO_{(g)}$ $(3)$ $H_{2(g)} + I_{2(g)} \rightleftharpoons 2HI_{(g)}$

For the reaction $2NO_{2(g)} \rightleftharpoons 2NO_{(g)} + O_{2(g)}$,the value of $K_c$ is $1.8 \times 10^{-6}$ at $184^{\circ}C$. Given $R = 0.083 \ L \cdot bar \cdot K^{-1} \cdot mol^{-1}$,compare $K_p$ and $K_c$ at $184^{\circ}C$.

An amount of solid $NH_4HS$ is placed in a flask already containing ammonia gas at a certain temperature and $0.50 \ atm$ pressure. Ammonium hydrogen sulphide decomposes to yield $NH_3$ and $H_2S$ gases in the flask. When the decomposition reaction reaches equilibrium,the total pressure in the flask rises to $0.84 \ atm$. The equilibrium constant for $NH_4HS$ decomposition at this temperature is