Based on the reactions, ascertain the valid algebraic relationship:
(i) C(g) +4H (g) CH4(g); 
Hr =x kJ mol-1
(ii) C(graphite) + 2H2 (g)   CH4; 
Hr  = y kJ mol-1

1. x = y 2. x = 2y
3. x > y 4. x < y

Subtopic:  Enthalpy & Internal energy |
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 enthalpies of elements in their standard states are taken as zero. The enthalpy of formation of a compound is-

1. Generally negative 2. Always positive
3. Zero 4. Never negative
Subtopic:  Thermochemistry |
 56%
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

Consider the following statement:

"A thermodynamic quantity is a state function"

The correct option is-

1. Used to determine heat changes

2. Whose value is independent of the path

3. Used to determine pressure-volume work

4. Whose value depends on temperature only.

 
Subtopic:  Classification of System, Extensive & Intensive Properties |
 84%
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

advertisementadvertisement

What is a necessary condition for an adiabatic process to occur?

1. ∆T = 0

2. ∆P = 0

3. q = 0

4. w = 0

Subtopic:  Thermodynamics' Properties and process |
 91%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The enthalpy of formation of all elements in their standard state is-

1. Unity 2. Zero
3. Less than zero 4. Different for each element
Subtopic:  Thermodynamics' Properties and process |
 81%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

U° for combustion of methane is –x kJ mol–1.

The value of H° for the same reaction would be:

1. = U°
2. > U°
3. < U°
4. =0

Subtopic:  Enthalpy & Internal energy |
 65%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

701 J of heat is absorbed by a system and 394 J of work is done by the system. The change in internal energy for the process is:

1. 307 J 2. -307 J
3. 1095 J 4. -701 J
Subtopic:  First Law of Thermodynamics |
 82%
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 reaction of cyanamide, NH2CN (s) with dioxygen, was carried out in a bomb calorimeter, and ∆U was found to be -742.7 kJ mol-1 at 298 K.
\(\small{\mathrm{NH}_2 \mathrm{CN}(\mathrm{s})+\frac{3}{2} \mathrm{O}_2(\mathrm{g}) \rightarrow \mathrm{N}_2(\mathrm{g})+\mathrm{CO}_2(\mathrm{g})+\mathrm{H}_2 \mathrm{O}(\mathrm{l})}\)

The enthalpy change for the reaction at 298 K would be:

1. -741.3 kJ mol-1
2. + 753.9 kJ mol-1
3. + 772. 7 kJ mol-1
4. -845. 1 kJ mol-1

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

The amount of heat needed to raise the temperature of 60.0 g of aluminium from 35°C to 55°C would be:

(Molar heat capacity of Al is \(24\) \(J\) \(\text{mol}^{- 1}\) \(K^{- 1}\))

1. \(1 . 07\) \(J\) 2. \(1 . 07\) \(kJ\)
3. \(106 . 7\) \(kJ\) 4. \(100 . 7\) \(kJ\)
Subtopic:  Thermodynamics' Properties and process |
 69%
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

advertisementadvertisement

The enthalpy of formation of COg, CO2g, N2Og , and N2O4g are –110 kJ mol-1, – 393 kJ mol-1, 81 kJ mol-1, and 9.7 kJ \(\text{mol}^{- 1}\) respectively. The value of \(\left(\Delta\right)_{r} H\) for the following reaction would be:

\(\mathrm{N_{2} O_{4 \left(g\right)} + 3 CO{\left(g\right)} \rightarrow N_{2} O_{\left(g\right)} + 3CO_{2 \left(g\right)}}\)

1. \(- 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) 2. \(\) \(+ 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\)
3. \(\) \(+ 824 . 9\) \(kJ\) \(\text{mol}^{- 1}\) 4. \(-\) \(345 . 4\) \(kJ\) \(\text{mol}^{- 1}\)
Subtopic:  Thermochemistry |
 76%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch