Name: Factors Affecting the Internal Energy
Uploaded: 2019-07-19
Duration: 3 min 47 s
Description: The internal energy of a thermodynamic system is the energy contained within it. Let's watch the video to learn more about the internal energy of a system.

Question

Obtain the relationship between

{ΔG}^{0}

of a reaction and the equilibrium constant.

Accepted Answer

Gibbs energy change for a chemical reaction is given by

$ΔG = ΔG ° + RTInQ$ ...(1)

Where, $ΔG °$ is standard Gibbs energy change that is, the Gibbs energy change when the reactants and products in a reaction are in their standard states. $Q$ is called reaction quotient. $Q$ is analogous to that of the equilibrium constant and involves nonequilibrium concentrations or partial pressures in case of a gaseous reaction.

Consider the reaction, $aA + bB \to cC + dD$ .

From equation (1),

$ΔG = ΔG ° + RT InQc or ΔG = ΔG ° + RT InQp . ΔG = ΔG \circ + RTln \frac{[C]^{c} [D]^{d}}{[A]^{a} [B]^{b}} or = ΔG ° + RTln \frac{P_{c} C \times P_{d} D}{P_{a} A \times P_{b} B} .$

When the reaction reaches equilibrium, $ΔG ° = 0$ and $Q_{c}$ and $Q_{p}$ become $K_{c}$ and $K_{p}$ , respectively.

Thus,

$∴ 0 = ΔG ° + RT {InK}_{c} or 0 = ΔG ° + RT {InK}_{p} . ∴ ΔG ° = — RT {InK}_{c} or ΔG ° = — RT {InK}_{p} . ∴ ΔG ° = — 2.303 RT \log_{10} K_{c} or ΔG ° = — 2.303 RT \log_{10} K_{p} .$

Obtain the relationship between ${ΔG}^{0}$ of a reaction and the equilibrium constant.

Important Questions on Chemical Thermodynamics

Learn and Prepare for any exam you want !

Obtain the relationship between ΔG0 of a reaction and the equilibrium constant.

Important Questions on Chemical Thermodynamics

Learn and Prepare for any exam you want !

Obtain the relationship between ${ΔG}^{0}$ of a reaction and the equilibrium constant.