Select Question Set:
Q. No.The second law of thermodynamics says:
1.
the efficiency of a heat engine can be unity.
2.
the heat released to the cold reservoir can be made zero.
3.
coefficient of performance can never be infinite for refrigerators.
4.
none of the above.
Subtopic: Second Law of Thermodynamics |
60%
Level 2: 60%+
Please attempt this question first.
Hints
Please attempt this question first.
The lowest possible temperature is:
1. \(0^\circ\text{C}\)
2. \(0^\circ \text{F} \)
3. \(-173^\circ \text{C} \)
4. \(0 ~\text{K}\)
1. \(0^\circ\text{C}\)
2. \(0^\circ \text{F} \)
3. \(-173^\circ \text{C} \)
4. \(0 ~\text{K}\)
Subtopic: Second Law of Thermodynamics |
79%
Level 2: 60%+
Please attempt this question first.
Hints
Please attempt this question first.
Consider the following reaction:
\(\mathrm{2H_2(g) + O_2(g) \rightarrow 2H_2O(g); ~\Delta_rH^\circ = -483.64~ kJ }\)
What is the enthalpy change (in KJ) for the decomposition of one mole of water?
\(\mathrm{2H_2(g) + O_2(g) \rightarrow 2H_2O(g); ~\Delta_rH^\circ = -483.64~ kJ }\)
What is the enthalpy change (in KJ) for the decomposition of one mole of water?
| 1. | 120.9 | 2. | 241.82 |
| 3. | 18 | 4. | 100 |
Subtopic: Thermochemistry |
89%
Level 1: 80%+
NEET - 2023
Hints
Three thermochemical equations are given below:
Based on the above equations, find out which one of the relationships given below is correct :
| (i) | C(graphite) + O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = x kJ mol–1 |
| (ii) | Cgraphite + 1/2 O2(g) \(\rightarrow\) CO(g); \(\Delta_{r}\)H° = y kJ mol–1 |
| (iii) | CO(g) + 1/2 O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = z kJ mol–1 |
Based on the above equations, find out which one of the relationships given below is correct :
| 1. | z = x + y | 2. | x = y + z |
| 3. | y = 2z – x | 4. | x = y – z |
Subtopic: Hess's Law |
79%
Level 2: 60%+
NEET - 2013
Hints
The \((P\text-V)\) diagram of a gas system undergoing a cyclic process is shown in the given figure. The work done by the gas during isobaric compression is:
1. \(150~\text J\)
2. \(-200~\text J\)
3. \(-400~\text J\)
4. \(-250~\text J\)
1. \(150~\text J\)
2. \(-200~\text J\)
3. \(-400~\text J\)
4. \(-250~\text J\)
Subtopic: Cyclic Process |
59%
Level 3: 35%-60%
Please attempt this question first.
Hints
Please attempt this question first.
Unlock IMPORTANT QUESTION
This question was bookmarked by 5 NEET 2025 toppers during their NEETprep journey. Get Target Batch to see this question.
✨ Perfect for quick revision & accuracy boost
Buy Target Batch
Access all premium questions instantly
The temperature of \(n\) moles of an ideal gas is increased from \(T\) to \(4T\) through a process for which pressure \(P=\frac aT,\) where \(a\) is a constant. The work done by the gas is: (\(R\) is universal gas constant)
| 1. | \(3nRT\) | 2. | \(6nRT\) |
| 3. | \(4nRT\) | 4. | \(9nRT\) |
Subtopic: Work Done by a Gas |
Level 3: 35%-60%
Please attempt this question first.
Hints
Please attempt this question first.
Determine \(\Delta U\) for the process where, one mole of an ideal gas at 300 K is expanded isothermally from 1 L to 10 L volume:
(Use R = 8.314 J K–1 mol–1)
(Use R = 8.314 J K–1 mol–1)
| 1. | 1260 J | 2. | 2520 J |
| 3. | 5040 J | 4. | 0 J |
Subtopic: First Law of Thermodynamics |
80%
Level 1: 80%+
NEET - 2022
Hints
A thermally insulated vessel contains an ideal gas of molecular mass \(M\) and a specific heat ratio of \(1.4.\) The vessel is moving with speed \(v\) and is suddenly brought to rest. Assuming no heat is lost to the surroundings, then the vessel temperature of the gas increases by:
(\(R=\) universal gas constant)
(\(R=\) universal gas constant)
| 1. | \(\dfrac{M v^2}{7 R} \) | 2. | \(\dfrac{M v^2}{5 R} \) |
| 3. | \(\dfrac{2M v^2}{7 R} \) | 4. | \(\dfrac{7M v^2}{5 R} \) |
Subtopic: Molar Specific Heat |
57%
Level 3: 35%-60%
Please attempt this question first.
Hints
Please attempt this question first.
A monoatomic gas performs a work of \(\dfrac{ Q} {4}\) where \(Q\) is the heat supplied to it. During this transformation, the molar heat capacity of the gas will be: (\(R\) is the gas constant.)
| 1. | \(R\) | 2. | \(2R\) |
| 3. | \(3R\) | 4. | \(4R\) |
Subtopic: Molar Specific Heat |
60%
Level 2: 60%+
JEE
Please attempt this question first.
Hints
Please attempt this question first.
A heat engine (Carnot engine) operates between a cold reservoir at temperature \(T_2=300\) K and a hot reservoir at temperature \(T_1.\) If it were to take \(100\) J of heat from the hot reservoir and deliver \(80\) J of heat to the cold reservoir in each cycle, the minimum temperature of the hot reservoir would be:
1. \(350\) K
2. \(375\) K
3. \(400\) K
4. \(450\) K
1. \(350\) K
2. \(375\) K
3. \(400\) K
4. \(450\) K
Subtopic: Carnot Engine |
87%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.
Select Question Set:
© 2025 GoodEd Technologies Pvt. Ltd.