Question

question 20 of 25
what is the value for δg at 5000 k if δh = -220 kj/mol and δs = -0.05 kj/(mol·k)?

a. -470 kj
b. 470 kj
c. 30 kj
d. -195 kj

Explanation:

Step1: Recall Gibbs - free energy formula

$\Delta G=\Delta H - T\Delta S$

Step2: Substitute given values

$\Delta H=- 220\ kJ/mol$, $T = 5000\ K$, $\Delta S=-0.05\ kJ/(mol\cdot K)$
$\Delta G=-220-(5000\times(-0.05))$

Step3: Calculate the result

$\Delta G=-220 + 250$
$\Delta G = 30\ kJ/mol$

Answer:

C. 30 kJ