One mole of an ideal monoatomic gas expands isothermally against constant external pressure of 1 atm from initial volume of 1L to a state where its final pressure becomes equal to external pressure. If initial temperature of gas is 300 K then total entropy change of system in the above process is :

[R = 0.082 L atm mol–1 K–1 = 8.3 J mo1–1K–1].

(1) 0

(2) Rln (24.6)

(3) Rln (2490)

(4) 32Rln(24.6)

Subtopic:  Spontaneity & Entropy |
 50%
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

At 1000 K water vapour at 1 atm. has been found to be dissociated into H2 and O2 to the extent of 3 x 10–6 %.Calculate the free energy decrease of the system, assuming ideal behaviour.

(1) –ΔG = 90,060 cal

(2) –ΔG = 20 cal

(3) –ΔG = 480 cal

(4) –ΔG = –45760 cal

Subtopic:  Spontaneity & Entropy |
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

An ideal gas is taken from the same initial pressure P1 to the same final pressure P2 by three different processes. If it is known that point 1 corresponds to a reversible adiabatic and point 2 corresponds to a single stage adiabatic then

(1) Point 3 may be a two stage adiabatic.

(2) the average K.E. of the gas is maximum at point 1

(3) Work done by surrounding in reaching point number '3' will be maximum

(4) If point4 and point 5 lie along a reversible isotherm then T5 < T1.

Subtopic:  2nd & 3rd Law of Thermodynamics |
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

During winters, moisture condenses in the form of dew and can be seen on plant leaves and grass. The entropy of the system in such cases decreases as liquids possess lesser disorder as compared to gases. With reference to the second law, which statement is correct, for the above process ?

(1) The randomness of the universe decreases

(2) The randomness of the surroundings decreases

(3) Increase is randomness of surroundings equals the decrease in randomness of system

(4) The increase in randomness of the surroundings is greater as compared to the decrease in randomnessof the system.

Subtopic:  Spontaneity & Entropy |
 50%
From NCERT
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

For which process will H° and G° be expected to be most similar.

(1) 2Al(s) + Al2O3(s) → 2Fe(s) + Al2O3(s)

(2) 2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)

(3) 2NO2(g) → N2O4(g)

(4) 2H2(g) + O2(g) → 2H2O(g)

Subtopic:  Spontaneity & Entropy |
 74%
From NCERT
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

A copper block of mass `m' at temperature 'T1' is kept in the open atmosphere at temperature `T2' where T2 > T1 . The variation of entropy of the copperblock with time is best illustrated by

(1)

(2)

(3)

(4)

Subtopic:  Spontaneity & Entropy |
 51%
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

The heat produced in calories by the combustion of one gram of carbon is called

1. Heat of combustion of carbon

2. Heat of formation of carbon

3. Calorific value of carbon

4. Heat of production of carbon

Subtopic:  Thermochemistry |
 65%
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

For the isothermal expansion of an ideal gas

(1) E and H increases

(2) E increases but H decreases

(3) H increases but E decreases

(4) E and H are unaltered

Subtopic:  2nd & 3rd Law of Thermodynamics |
 67%
From NCERT
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints
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NEET 2023 - Target Batch - Aryan Raj Singh

If a refrigerator's door is opened, then we get

(1) Room heated

(2) Room cooled

(3) More amount of heat is passed out

(4) No effect on room

Subtopic:  Enthalpy & Internal energy |
 62%
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints

Point out the wrong statement in relation to enthalpy

1. It is a state function

2. It is an intensive property

3. It is independent of the path followed for the change

4. Its value depends upon the amount of substance in the system

Subtopic:  Classification of System, Extensive & Intensive Properties |
 70%
From NCERT
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NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh