Two elementary reactions have equilibrium constants and

CHEMISTRY · Subjective · A Level · Chemistry · Thermodynamics · Thermodynamics

Problem

Two elementary reactions have equilibrium constants

K_1 = 4.0\times10^{-3}

and

K_2 = 2.0\times10^{2}

, respectively. The reactions are added to obtain an overall balanced equation. State whether the standard Gibbs free-energy change

\Delta G^{\circ}

for the overall reaction is positive, negative, or approximately zero at 298 K, and briefly explain your reasoning.