Question

Consider the following reaction:

CO2(g)+CCl4(g)⇌2COCl2(g).
Calculate ΔG for this reaction at 25 ∘C under the following conditions.

PCO2= 0.140 atm
PCCl4= 0.160 atm
PCOCl2= 0.745 atm

Answer 1

Answer: -7956 J

Explanation:

Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as
`K_(eq)`

`CO_2(g)+CCl_4(g)\rightleftharpoons 2COCl_2(g)`

The expression for
`K_(eq)` is written as:

`K_(eq)=((p_(COCl_2))^2)/(p_(CO_2)* p_(CCl_4)^1)`

`K_(eq)=([0.745]^2)/(0.140* 0.160)`

`K_(eq)=24.8`

The Gibbs free energy is related to equilibrium constant by following relation:

`\Delta G=-2.303RTlog K`

R = gas constant = 8.314 J/Kmol

T = temperature in kelvin =
`25^0C=25+273=298K`

K = equilibrium constant

`\Delta G=-2.303RTlog K`

`\Delta G=-2.303* 8.314* 298* log(24.8)`

`\Delta G=-7956J`

Thus ΔG for this reaction at 25 ∘C is -7956 J