148515
There is no change in internal energy of an ideal gas when it undergoes.
1 Isothermal expansion
2 Adiabatic expansion
3 Free expansion
4 Isobaric expansion
Explanation:
C Free expansion :- The expansion of a gas against vacuum (zero resistance) is known as free expansion. $\mathrm{W}=0, \mathrm{dQ}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{W}$ $0=\mathrm{dU}+0$ $\mathrm{U}_{\mathrm{f}}=\mathrm{U}_{\mathrm{i}}=0$ $\mathrm{U}_{\mathrm{f}}=\mathrm{U}_{\mathrm{i}}$ $\because$ For free expansion there is no change in internal energy of an ideal gas when it undergoes.
AP EAMCET (18.09.2020) Shift-I
Thermodynamics
148516
Assertion: In free expansion of an ideal gas, the entropy increases. Reason: Entropy increases in all natural process
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.
Explanation:
A Expansion of a gas against vacuum is called free or unrestricted expansion process. Pressure $\rightarrow$ decrease, Volume $\rightarrow$ increase $\mathrm{dQ} \& \mathrm{dW}=0, \quad \mathrm{U}=$ Constant enthalpy constant \& but entropy increases. So, option (a) is correct. Heat Engine, Carnot's Cycle and Refrigeration (COP)
148515
There is no change in internal energy of an ideal gas when it undergoes.
1 Isothermal expansion
2 Adiabatic expansion
3 Free expansion
4 Isobaric expansion
Explanation:
C Free expansion :- The expansion of a gas against vacuum (zero resistance) is known as free expansion. $\mathrm{W}=0, \mathrm{dQ}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{W}$ $0=\mathrm{dU}+0$ $\mathrm{U}_{\mathrm{f}}=\mathrm{U}_{\mathrm{i}}=0$ $\mathrm{U}_{\mathrm{f}}=\mathrm{U}_{\mathrm{i}}$ $\because$ For free expansion there is no change in internal energy of an ideal gas when it undergoes.
AP EAMCET (18.09.2020) Shift-I
Thermodynamics
148516
Assertion: In free expansion of an ideal gas, the entropy increases. Reason: Entropy increases in all natural process
1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.
Explanation:
A Expansion of a gas against vacuum is called free or unrestricted expansion process. Pressure $\rightarrow$ decrease, Volume $\rightarrow$ increase $\mathrm{dQ} \& \mathrm{dW}=0, \quad \mathrm{U}=$ Constant enthalpy constant \& but entropy increases. So, option (a) is correct. Heat Engine, Carnot's Cycle and Refrigeration (COP)
