For a reversible chemical reaction at equilibrium involving two reactants,if the concentrations of the reactants are doubled,what happens to the equilibrium constant $(K_c)$?

What is homogeneous equilibrium? Give examples.

For the reaction $N_2 + 3H_2 \rightleftharpoons 2NH_3$,the value of $K_c$ does not depend on: $(a)$ Initial concentration of reactants $(b)$ Pressure $(c)$ Temperature $(d)$ Catalyst

For the reaction $H_2O_{(s)} \rightleftharpoons H_2O_{(l)}$ at $0\,^\circ C$ and normal pressure:

Predict which of the following reactions will have an appreciable concentration of both reactants and products:
$(a)$ $Cl_{2(g)} \longleftrightarrow 2Cl_{(g)};$ $K_{c}=5 \times 10^{-39}$
$(b)$ $Cl_{2(g)}+2NO_{(g)} \longleftrightarrow 2NOCl_{(g)};$ $K_{c}=3.7 \times 10^{8}$
$(c)$ $Cl_{2(g)}+2NO_{2(g)} \longleftrightarrow 2NO_{2}Cl_{(g)};$ $K_{c}=1.8$

In a reversible reaction $A \overset{k_1}{\underset{k_2}{\longleftrightarrow}} B$,the initial concentrations of $A$ and $B$ are $a$ and $b$,and the equilibrium concentrations are $(a - x)$ and $(b + x)$ respectively. Express $x$ in terms of $k_1, k_2, a$,and $b$.