Entropy Change in Isothermal Process

Q.

The entropy change involved in the isothermal reversible expansion of 2 mole of an ideal gas from a volume of $10d{m}^3$ to a volume of $100d{m}^3$ at ${27}^{\circ }C$ is :

1. 38.3 J mol⁻¹ K⁻¹

2. 35.8 J mol⁻¹ K⁻¹

3. 32.3 J mol⁻¹ K⁻¹

4. 42.3 J mol⁻¹ K⁻¹

Q. What is the entropy change involved in the isothermal expansion of 5 mol of ideal gas from a volume of 10L to 100L at 300 K?

1. 
2. 
3. 
4. 

Q.

The entropy change involved in the isothermal reversible expansion of $2\mathrm{moles}$ of an ideal gas from a volume of $10{\mathrm{dm}}^3$ at $27°\mathrm{C}$ is to a volume of $100{\mathrm{dm}}^3$ at $27°\mathrm{C}$ is?

Q. 5 moles of an ideal gas expand reversibly from a volume of 8 $d{m}^3$ to 80 $d{m}^3$ at a temperature of ${27}^{\circ }C$. Calculate the change in entropy.

1. $70.26J{K}^{-1}$
2. $82.55J{K}^{-1}$
3. $95.73J{K}^{-1}$
4. $107.11J{K}^{-1}$

Q. Assertion (A): $\Delta U=0$ for a reversible as well as irreversible expansion of an ideal gas under isothermal conditions, whereas $S_{total}\ne 0$ for an irreversible process.

1. The Assertion is correct but Reason is not correct
2. The Assertion is not correct but Reason is correct
3. Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion
4. Both Assertion and Reason are correct but the Reason is not the correct explanation of the Assertion

Q. What is the entropy change when 1-mole oxygen gas expands isothermally and reversibly from an initial volume of 10L to 100L at 300 K?

1. 19.14 J $K^{-1}$
2. 29.12 J $K^{-1}$
3. 109.12 J $K^{-1}$
4. 10 J $K^{-1}$

Q. What is the entropy change when 1 mole oxygen gas expands isothermally and reversibly from an initial volume of 10 L to 100 L at 300 K?

1. $19.14J{K}^{-1}$
2. $109.12J{K}^{-1}$
3. $29.12J{K}^{-1}$
4. $10J{K}^{-1}$

Q. Oxygen gas weighing $64g$ is expanded from $1atm$ to $0.1atm$ at $30{}^{o}C.$ Calculate entropy change, assuming the gas to be ideal

1. $34.29J{K}^{-1}$
2. $38.29J{K}^{-1}$
3. $44.29J{K}^{-1}$
4. $48.29J{K}^{-1}$

Q. Calculate the change in entropy of 2 moles of an ideal gas upon isothermal expansion at 243.6 K from 20 litre until the pressure becomes 1 atm.

1. $-4.5cal/K$
2. $-1.25cal/K$
3. $1.25cal/K$
4. $2.77cal/K$

Q. The change in entropy of 2 moles of an ideal gas upon isothermal expansion at 243.6 K from 20 L until the pressure becomes 1 atm is :

1. $1.385cal/K$
2. $-1.2cal/K$
3. $-1.2cal/K$
4. $2.77cal/K$