A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 37.0ºC. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be-
(R = 8.314 J/mol K) (ln 7.5 = 2.01)

1. q = +208 J, w = -208 J 2. q = -208 J, w = -208 J
3. q = -208 J, w = + 208 J 4. q = +208 J, w = + 208 J

Subtopic:  First Law of Thermodynamics |
 83%
Level 1: 80%+
Hints

Reversible expansion of an ideal gas under isothermal and adiabatic conditions are shown in the figure:

AB→Isothermal expansion

AC→Adiabatic expansion

Which of the following options is not correct?

1. \(\Delta S_{\text {isothermal }}>\Delta S_{\text {adiabatic }} \) 2. \(T_A=T_B \)
3. \(W_{\text {isothermal }}>W_{\text {adiabatic }} \) 4. \(T_C>T_A\)
Subtopic:  2nd & 3rd Law of Thermodynamics |
 55%
Level 3: 35%-60%
NEET - 2019
Hints

What is the amount of work done by an ideal gas, if the gas expands isothermally from \(10^{-3}~m^3\) to \(10^{-2}~m^3\) at \(300~K\)against a constant pressure of \(10^{5}~Nm^{-2}\)?

1. \(+270 ~kJ\) 2. \(–900 ~J\)
3. \(+900 ~kJ\) 4. \(–900~ kJ\)
Subtopic:  First Law of Thermodynamics |
 72%
Level 2: 60%+
NEET - 2019
Hints

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Which is an extensive property?

1. Temperature 2. Chemical potential
3. Gibbs free energy 4. Molar volume
Subtopic:  Classification of System, Extensive & Intensive Properties |
 68%
Level 2: 60%+
Hints

The pair of isochoric among the transformation of state is:

1. K to L and L to M

2. L to M and N to K

3. L to M and M to N

4. M to N and N to K

Subtopic:  Classification of System, Extensive & Intensive Properties |
 88%
Level 1: 80%+
Hints

Find the enthalpy of formation of FeS when 2.1 g of Fe combines completely with sulfur and releases 3.77 kJ of heat.

1. – 3.77 2. – 1.79
3. – 100.5 4. None of the above
Subtopic:  Enthalpy & Internal energy |
 52%
Level 3: 35%-60%
Hints

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Hydrolysis of sucrose is given by the following reaction

Sucrose + H2O ⇌ Glucose + Fructose

If the equilibrium constant (Kc) is 2×1013 at 300 K, the value of ∆rG⊝ at the same temperature will be:

1. 8.314 J mol–1 K–1×300 K×ln (2×1013)

2. 8.314 J mol–1 K–1×300 K×ln (3×1013)

3. –8.314 J mol–1 K–1×300 K×ln (4×1013)

4. –8.314 J mol–1 K–1×300 K×ln (2×1013)

Subtopic:  Gibbs Energy Change |
 81%
Level 1: 80%+
NEET - 2020
Hints
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For the reaction, 2Cl(g) → Cl2(g), the correct option is:
1. \(\Delta_{\mathrm{r}} \mathrm{H}>0\) and \(\Delta_{\mathrm{r}} \mathrm{S}<0 \) 2. \(\Delta_{\mathrm{r}} \mathrm{H}<0\) and \( \Delta_{\mathrm{r}} \mathrm{S}>0 \)
3. \(\Delta_{\mathrm{r}} \mathrm{H}<0 \) and \(\Delta_{\mathrm{r}} \mathrm{S}<0 \) 4. \(\Delta_{\mathrm{r}} \mathrm{H}>0\) and \( \Delta_{\mathrm{r}} \mathrm{S}>0\)
Subtopic:  Enthalpy & Internal energy | Spontaneity & Entropy |
 61%
Level 2: 60%+
NEET - 2020
Hints

The correct option for free expansion of an ideal gas under adiabatic condition is:

1.  q=0, ∆T<0 and w>0

2.  q<0, ∆T=0 and w=0

3.  q>0, ∆T>0 and w>0

4.  q=0, ∆T=0 and w=0

Subtopic:  2nd & 3rd Law of Thermodynamics |
 77%
Level 2: 60%+
NEET - 2020
Hints

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The solubility of a solute in water varies with temperature and is given as S=Ae-∆H/RT.

Here, ∆H is enthalpy of the solution. For the given solute variation of log, S with temperature can be shown by the figure given below.

This solute may be

1. CaSO4 

2. CuSO4 

3. CuSO45H2O

5. MgO

Subtopic:  Spontaneity & Entropy |
 65%
Level 2: 60%+
Hints