# Determine the enthalpy change for the specified reaction: 2H2O2(l) $\to$ 2H2O(l) + O2(g). (Given the heat of formation of H2O2(l) and H2O(l) are –188 and –286 kJ/mol respectively)        1. –196 kJ/mol 2. +196 kJ/mol 3. +948 kJ/mol 4. –948 kJ/mol

Subtopic:  Enthalpy & Internal energy |
68%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

One mole of a non-ideal gas undergoes a change of state (2.0 atm, 3.0 L, 95 K)$\to$(4.0 atm, 5.0 L, 245 K) with a change in internal energy, $∆$U = 30.0 L atm. The change in enthalpy ($∆$H) of the process in L atm is:

1. 40.0

2. 42.3

3. 44.0

4. not defined, because pressure is not constant

Subtopic:  First Law of Thermodynamics |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

According to the law, a perfect crystal's entropy is 0 at absolute zero, which is:

1. The first law

2. Second law

3. Third law

4. None of the above

Subtopic:  Spontaneity & Entropy |
59%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

At constant pressure and temperature, the direction of any chemical reaction is one where the...... decrease.

1. Entropy

2. Enthalpy

3. Gibbs energy

4. None of the above

Subtopic:  Spontaneity & Entropy |
54%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The work done by a mass less piston in causing an expansion $∆$V (at constant temperature), when the opposing pressure, P is variable, is given by:

1. W= $-\int \mathrm{P}∆\mathrm{V}$

2. W=0

3. W= -P$∆$V

4. none of these

Subtopic:  2nd & 3rd Law of Thermodynamics |
64%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Entropy decreases during:

1. crystallization of sucrose from solution

2. rusting of iron

3. melting of ice

4. vaporization of camphor

Subtopic:  Spontaneity & Entropy |
72%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Entropy change of vaporization at constant pressure is given by:

1.

2. $∆{\mathrm{S}}_{\mathit{\left(}v\mathit{\right)}}=\frac{∆{\mathrm{U}}_{v}}{\mathrm{T}}$

3.

4. None of the above

Subtopic:  Spontaneity & Entropy |
75%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

What is the entropy change for the reaction given below,

2H2 (g) + O2 (g) $\to$2H2O(l)

at temperature 300 K? Standard entropies of H2 (g), O2(g) and H2O(l) are 126.6, 201.20 and 68.0 JK-1mol-1 respectively.

1. -318.4 JK-1mol-1                           .

2. 318.4 JK-1mol-1

3. 31.84 JK-1mol-1

4. none of these

Subtopic:  Spontaneity & Entropy |
72%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

If S$°$ for H2, Cl2 and HCl are 0.13, 0.22 and 0.19 kJ K-1mol-1 respectively. The total change in standard entropy for the reaction, H2 + Cl2 $\to$2HCl is:

1. 30 J K-1mol-1

2. 40 J K-1mol-1

3. 60 J K-1mol-1

4. 20 J K-1mol-1

Subtopic:  Spontaneity & Entropy |
79%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

The direct conversion of A to B is difficult and thus it is converted by path A$\to$C$\to$D$\to$B. Given

(Where e.u. is the entropy unit)
then $∆{\mathrm{S}}_{\mathrm{A}\to \mathrm{B}}$ would be:

1. +60 e.u

2. +100 e.u

3. -60 e.u

4. -100 e.u

Subtopic:  Hess's Law |
60%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints