For the reaction

CHEMISTRY · Single correct · A Level · Chemistry · Thermodynamics · Thermodynamics

Problem

For the reaction

2\,\mathrm{CO}(g) + \mathrm{O_2}(g) \rightarrow 2\,\mathrm{CO_2}(g)

, the standard Gibbs free energy change at 298 K is

\Delta G^\circ = -514\,\text{kJ}

. What is

\Delta G^\circ

for the reaction

\mathrm{CO}(g) + \tfrac12\,\mathrm{O_2}(g) \rightarrow \mathrm{CO_2}(g)

at the same temperature? (a)

-514\,\text{kJ}

(b)

-1.028\times10^{3}\,\text{kJ}

(c)

-257\,\text{kJ}

(d)

+257\,\text{kJ}