Question

Phosphorus pentachloride decomposes at higher temperatures.

PCl₅(g) ⇄ PCl₃(g) + Cl₂(g)

An equilibrium mixture at some temperature consists of

3.03 g PCl₅, 208.23 g/mol
4.86 g PCl₃, 137.33 g/mol
3.59 g Cl₂, 70.91 g/mol

in a 1.00-L flask.

If you add 1.31 g of Cl₂, how will the equilibrium be affected and what will the concentration of PCl₅ be when equilibrium is reestablished?

shift left

shift right

no shift will occur

[PCl₅] =   mol/L

Answer 1

We’re given the following equilibrium:

PCl5(g)⇌ PCl3(g) + Cl2(g)

First, we are asked to determine the equilibrium shift when Cl2 is added.

• According to Le Chatelier’s Principle, once a system in equilibrium is disturbed, the system will readjust and relieve the stress introduced to maintain its equilibrium.

• Cl2 is in the product side. Adding Cl2 to the system means the amount of products increased.

Therefore, the reaction would shift to the left to maintain equilibrium.

HALF IS ANSWER IS MENTIONED BELOW IN IMAGE.