For the reaction $2HI_{(g)} \rightleftharpoons H_{2(g)} + I_{2(g)}$,the equilibrium constant $K$ at room temperature is $2.85$,and at $698 \ K$ it is $1.4 \times 10^{-2}$. This indicates that:

For a reversible reaction,if the concentration of the reactants is reduced to half,the equilibrium constant will be.........

In the given reaction $N_2 + O_2 \rightleftharpoons 2NO$,equilibrium means that

Explain the types of physical equilibrium with examples.

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 at equilibrium between two reactants,if the concentration of the reactants is doubled,the equilibrium constant ..........