Question

(POCl3)At a moderately elevated temperature, phosphoryl chloride$\mathbf{\left(}{\mathbf{POCl}}_{\mathbf{3}}\mathbf{\right)}$can be produced in the vapor phase from the gaseous elements. Write a balanced chemical equation and an equilibrium expression for this system. Note that gaseous phosphorus consists of P₄(POCl3)molecules at moderate temperatures.

Short answer

The balanced equation for the reaction is:

${\mathrm{P}}_4\left(g\right)+2{\mathrm{O}}_2\left(g\right)+6{\mathrm{Cl}}_2\left(g\right)\rightleftharpoons 4{\mathrm{POCl}}_3$

And the equilibrium expression is$\mathrm{K}=\left[\frac{{\left({\mathrm{P}}_{{\mathrm{POCl}}_3}\right)}^4}{\left({\mathrm{P}}_{{\mathrm{P}}_4}\right){\left({\mathrm{P}}_{{\mathrm{O}}_2}\right)}^2{\left({\mathrm{P}}_{{\mathrm{Cl}}_2}\right)}^6}\right]$

Step-by-step solution

Given information

The elements in the vapor phase are P₄, O_2,and Cl₂ from phosphoryl chloride(POCl₃).

Concept of the law of mass action

The rate of a chemical reaction at a particular temperature and moment is directly proportional to the product of the active masses of the reactants, according to the law.

For a gas phase reaction-$\mathbf{aA}\mathbf{+}\mathbf{bB}\mathbf{\rightleftharpoons }\mathbf{cC}\mathbf{+}\mathbf{dD}$

Calculate equilibrium expression

The unbalanced equation is as follows: