Question

1 mole of an ideal gas at 25 degree Celsius is subjected to expand reversibly 10 times of its initial volume the change in entropy of expansion is

Answer 1

Answer : The change in Entropy of expansion = 19.147 J/K

Solution : Given,

Number of moles = 1 mole

Temperature = $25^{0} C$

Let, Initial volume = 1 L  then

Final volume = 10 times of initial volume = 10 L

Formula used for change in entropy for reversibly isothermal exapansion of an ideal gas is,

ΔS = $\frac{q}{T}$ = $\frac{2.303\times n\times R\times {T}\times log\left (\frac{V_{final} }{V_{initial}}\right )}{T}$ = ${2.303\times n\times R\times log\left (\frac{V_{final} }{V_{initial}}\right )}$

Now put all the given values in above formula, we get

ΔS = ${2.303\times 1mole\times 8.314J/molK\times log\left (\frac{10L}{1L}\right )}$ = 19.147 J/K

Answer 2

Answer:

Zero

Explanation:

The entropy change in an isolated system is always 0, when adiabatic expansion/compression takes place.