91Ó°ÊÓ

Ammonium chloride is an inorganic compound with the formula NH₄Cl and a white crystalline salt that is highly soluble in water. Solutions of ammonium chloride are mildly acidic. In its naturally occurring mineralogic form, it is known as sal ammoniac.

Calculate the equilibrium constant K_p for decomposition of the NH₄Cl

NH₄ Cl (s)⇌ NH₃ (g) + HCl(g)

K_p is calculated

\({K_p} = \frac{{p{{\left( {{{\rm{N}}_3}} \right)}_{eq}} \cdot p{{(HCl)}_{eq}}}}{1}\)

Equilibrium pressure for the \({\rm{N}}{{\rm{H}}_3}:\)

\(p{\left( {{\rm{N}}{{\rm{H}}_3}} \right)_{{\rm{eq}}}} = 1.75{\rm{atm}}\)

The equilibrium pressure of the\({\rm{HCl}}\).

\(\begin{array}{{}{}}{{\rm{\;p/atm\;}}}&{{\rm{N}}{{\rm{H}}_3}}&{{\rm{HCl}}}\\{{\rm{\;initial\;}}}&0&0\\{{\rm{\;change\;}}}&{ + x}&{ + x}\\{{\rm{\;equilibrium\;}}}&{1.75}&{0 + x}\end{array}\)

\(\begin{array}{{}{}}{x = 1.75{\rm{atm}}}\\{p{{(HCl)}_{{\rm{eq\;}}}} = 1.75{\rm{atm}}}\end{array}\)

We can now calculate\({K_p}\)

\(\begin{array}{{}{}}{{K_p} = 1.75 \cdot 1.75}\\{{K_p} = 3.06}\end{array}\)

Value of the equilibrium constant \({K_p} = 3.06\)