Question

Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas. pcl3(g) + cl2(g) equilibrium reaction arrow pcl5(g) a gas vessel is charged with a mixture of pcl3(g) and cl2(g), which is allowed to equilibriate at 450 k. at equilibrium the partial pressures of the three gases are ppcl3 = 0.124 atm, pcl2 = 0.157 atm, and ppcl5 = 1.30 atm.

Answer 1

The question is incomplete, here is the complete question:

Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas:

$PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$

A gas vessel is charged with a mixture of $PCl_3(g)$ and $Cl_2(g)$, which is allowed to equilibriate at 450 K. At equilibrium the partial pressures of the three gases are $p_{PCl_3(g)}$ = 0.126 atm , $p_{Cl_2(g)}$ = 0.156 atm , and $p_{PCl_5(g)}$ = 1.60 atm. What is the value of $K_p$ at this temperature?

Answer: The $K_p$ for the given reaction is 81.4

Explanation:

For the given chemical equation:

$PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$

The expression of $K_p$ for above reaction follows:

$K_p=\frac{p_{PCl_5}}{p_{Cl_2}\times p_{PCl_3}}$

We are given:

$p_{PCl_5}=1.60atm\\p_{PCl_3}=0.126atm\\p_{Cl_2}=0.156atm$

Putting values in above equation, we get:

$K_p=\frac{1.60}{0.156\times 0.126}\\\\K_p=81.4$

Hence, the $K_p$ for the given reaction is 81.4