Question

an exothermic reaction or a certain process at 300.0 K, ΔG = -77.0 kJ/mol and ΔH = -56.9 kJ/mol. Find the entropy change for this process. Enter your answer in Joules/mol K rounded to the nearest whole number (ones place).

Answer 1

Answer: The change in entropy for the given system is $7\times 10^1J/mol.K$

Explanation:

To calculate the entropy change for given Gibbs free energy, we use the equation:

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

where,

$\Delta G$ = Gibbs free energy = -77.0 kJ/mol = -77000 J/mol    (Conversion factor: 1 kJ = 1000 J)

$\Delta H$ = change in enthalpy = -56.9 kJ/mol = -56900 J/mol

T = temperature = 300 K

$\Delta S$ = change in entropy = ?

Putting values in above equation, we get:

$-77000J/mol=-56900-(300K\times \Delta S)\\\\\Delta S=\frac{-56900+77000}{300}=67J/mol.K=7\times 10^1J/mol.K$

Hence, the change in entropy for the given system is $7\times 10^1J/mol.K$