Chemistry - Chemical Equilibrium Question with Solution | TestHub

If the composition of the system does not change with time, the system is said to be in chemical equilibrium. It is the state in which the net reaction of a system is zero. In other words, we can say that in reversible reactions, a stage is reached when the rate of transformation of reactants into products equals the rate of transformation of products into reactants. At this stage, the composition of reactants and products does not change with time. This does not mean that the reaction has ceased, as both reverse and forward reactions are still taking place but with equal rates. Such equilibria are called dynamic equilibria.

Let us consider a reaction of the type, ⇌

$A_{\left(g\right)}+B_{\left(g\right)}\rightleftharpoons C_{\left(g\right)}+D_{\left(g\right)}$

$K_c=\frac{\left[C\right]\left[D\right]}{\left[A\right]\left[B\right]}$

where $K_{}$ is the equilibrium constant when the ratio of the concentrations of the product to reactants.

$K_P=\frac{P_C\times P_D}{P_A\times P_B}$

where $K_P$is the equilibrium constant for the ratio of partial pressure and of products to reactants. The relation between $K_P$ and $K_C$ is as follows:

$K_P=K_C(RT{)}^{\Delta n}$.