For the reaction $x \rightleftharpoons y$,which of the following factors will affect the value of $[\text{Product}] / [\text{Reactant}]^{-1}$ at equilibrium?

How can you predict the direction of a reaction by comparing the values of the equilibrium constant $K_{c}$ and the reaction quotient $Q_{c}$?
$(i)$ Net reaction proceeds in the forward direction,
$(ii)$ Net reaction proceeds in the backward direction,
$(iii)$ No net reaction occurs.

The equilibrium constant expression for the reaction $P_{4(s)} + 5O_{2(g)} \rightleftharpoons P_4O_{10(s)}$ is:

For the reaction $2HI \rightleftharpoons H_2 + I_2$,the equilibrium constant is $K_1 = 0.25$. What is the value of $K_2$ for the reaction $H_2 + I_2 \rightleftharpoons 2HI$?

For the reaction $A_{(g)} + B_{(g)} \rightleftharpoons 2 C_{(g)}$; $K_{c} = 4$. If equilibrium concentration of $A_{(g)}$ and $B_{(g)}$ are found to be $0.1 \ M$ and $0.4 \ M$ respectively. Determine equilibrium concentration of $C_{(g)}$. (in $M$)

The equilibrium constant expression for a gas reaction is,
$K_{C} = \frac{[NH_{3}]^{4}[O_{2}]^{5}}{[NO]^{4}[H_{2}O]^{6}}$
Write the balanced chemical equation corresponding to this expression.