At a given temperature, 4.06 atm of H2 and 3.5 atm of Cl2 are mixed and allowed to come to equilibrium. The equilibrium pressure of HCl is found to be 1.418 atm. Calculate Kp for the reaction at this temperature. H2(g) + Cl2(g) <=> 2 HCl(g)

Equilibrium constant in terms of partial pressure is defined as the ratio of partial pressures of the products and the reactants each raised to the power their stoichiometric ratios. It is expressed as [tex]K_p[/tex]

For a general chemical reaction:

[tex]aA+bB\rightarrow cC+dD[/tex]

The expression for [tex]K_p[/tex] is written as:

[tex]K_p=\frac{p_{C}^cp_{D}^d}{p_{A}^ap_{B}^b}[/tex]

For the given chemical equation:

[tex]H_2(g)+Cl_2(g)\rightleftharpoons 2HCl(g)[/tex]

The expression for [tex]K_p[/tex] for the following equation is:

[tex]K_p=\frac{(p_{HCl})^2}{(p_{H_2)}(p_{Cl_2})}[/tex]

We are given:

[tex]p_{HCl}=1.418atm\\p_{H_2}=4.06atm\\p_{Cl_2}=3.5atm[/tex]

Putting values in above equation, we get:

[tex]K_p=\frac{(1.418)^2}{(4.06)\times (3.5)}\\\\K_p=0.1415[/tex]

The value of [tex]K_p[/tex] for the given chemical reaction is 0.1415