Question

Consider two insulated chambers a,b of same volume connected by a closed knob s. 1 mole of perfect gas is confined in chamber a. What is the change in entropy of gas when knob s is opened ?

Answer 1

Answer: 5.76 J/K

Explanation:

Entropy is the measure of randomness or disorder of a system.

To calculate the entropy change for isothermal expansion process, we use the equation:

$\Delta S=nR\ln(\frac{V_2}{V_1})$

where,

$\Delta S$ = Entropy change

n = number of moles = 1 mole

R = Gas constant = 8.314 J/mol.K

$V_1$ = initial volume = v

$V_2$ = final volume = 2v

Putting values in above equation, we get:

$\Delta S = 1mol\times 8.314J/mol.K\times \ln(\frac{2v}{v})\\\\\Delta S=5.76J/K$

Hence, the entropy change of the process is 5.76 J/K