The unit of the equilibrium constant for the reversible reaction $H_2 + I_2 \rightleftharpoons 2HI$ is:

For the reaction $CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$,which of the following expressions for the equilibrium constant $K_p$ is correct?

An equilibrium mixture of the reaction $2H_2S_{(g)} \rightleftharpoons 2H_{2(g)} + S_{2(g)}$ had $0.5 mol$ $H_2S$,$0.10 mol$ $H_2$,and $0.4 mol$ $S_2$ in a $1 L$ vessel. The value of the equilibrium constant $(K_c)$ in $mol L^{-1}$ is:

Before any reaction takes place,the value of the reaction quotient $(Q_c)$ is ......

For the reaction $N_2O_2 \rightleftharpoons 2NO$,the value of the concentration equilibrium constant is .......

If the equilibrium constant for the reaction $A + 3B \rightleftharpoons 2C$ is $K_1$,then the equilibrium constant $K_2$ for the reaction $2C \rightleftharpoons A + 3B$ should be: