
Which of the following is zero during the adiabatic expansion of the gas?
A. \[{\rm{\Delta T}}\]
B. \[{\rm{\Delta S}}\]
C. \[{\rm{\Delta E}}\]
D. None of these
Answer
164.1k+ views
Hint: A process is said to be adiabatic if there is no heat transfer in a system during any process step. In this process heat, q=0. During the expansion process, the system performs work on the surroundings.
Complete Step by Step Solution:
System is defined as any specified amount of matter under analysis divided from the rest of the universe with a bounding surface.
A system may consist of one or more substances.
In adiabatic expansion, no heat is enabled to come into or take off from the system.
Hence, q=0.
From the first law of thermodynamics, we know that
\[\Delta {\rm{U = q + w}}\]
So, \[\Delta {\rm{U = 0 + w}}\] or \[\Delta {\rm{U = w}}\]
A. \[{\rm{\Delta T}}\]
In an expansion process, work is done by the system on the surroundings.
So, the work done is negative.
Accordingly, internal energy decreases as the work is done at the expense of internal energy.
So, \[{\rm{\Delta E}}\]is negative.
We know that internal energy relies on the movement and configuration of particles which in turn rely on temperature.
So, if \[{\rm{\Delta E}}\] is negative then \[{\rm{\Delta T}}\] is negative.
We see that temperature change is negative and not zero.
So, A is incorrect.
B. \[{\rm{\Delta S}}\]
The entropy change of a system is
\[{\rm{\Delta S = }}\dfrac{{\rm{q}}}{{\rm{T}}}\]
As q=0, \[{\rm{\Delta S}}\]=0.
So, B is correct.
C. \[{\rm{\Delta E}}\]
In this expansion process, work is done by the system on the surroundings.
So, w is negative.
Internal energy decreases as the work is done at the expense of internal energy.
So, \[{\rm{\Delta E}}\] is negative, not zero.
So, C is incorrect.
So, option B is correct.
Note: If there is adiabatic compression, then work is done on the system
by the surroundings. This work is stored in the system in the form of internal energy.
In this case, work done is positive and hence the change in internal energy, \[{\rm{\Delta E}}\] is positive i.e., there would be an increase in internal energy. Due to this, there will be an increase in temperature.
Complete Step by Step Solution:
System is defined as any specified amount of matter under analysis divided from the rest of the universe with a bounding surface.
A system may consist of one or more substances.
In adiabatic expansion, no heat is enabled to come into or take off from the system.
Hence, q=0.
From the first law of thermodynamics, we know that
\[\Delta {\rm{U = q + w}}\]
So, \[\Delta {\rm{U = 0 + w}}\] or \[\Delta {\rm{U = w}}\]
A. \[{\rm{\Delta T}}\]
In an expansion process, work is done by the system on the surroundings.
So, the work done is negative.
Accordingly, internal energy decreases as the work is done at the expense of internal energy.
So, \[{\rm{\Delta E}}\]is negative.
We know that internal energy relies on the movement and configuration of particles which in turn rely on temperature.
So, if \[{\rm{\Delta E}}\] is negative then \[{\rm{\Delta T}}\] is negative.
We see that temperature change is negative and not zero.
So, A is incorrect.
B. \[{\rm{\Delta S}}\]
The entropy change of a system is
\[{\rm{\Delta S = }}\dfrac{{\rm{q}}}{{\rm{T}}}\]
As q=0, \[{\rm{\Delta S}}\]=0.
So, B is correct.
C. \[{\rm{\Delta E}}\]
In this expansion process, work is done by the system on the surroundings.
So, w is negative.
Internal energy decreases as the work is done at the expense of internal energy.
So, \[{\rm{\Delta E}}\] is negative, not zero.
So, C is incorrect.
So, option B is correct.
Note: If there is adiabatic compression, then work is done on the system
by the surroundings. This work is stored in the system in the form of internal energy.
In this case, work done is positive and hence the change in internal energy, \[{\rm{\Delta E}}\] is positive i.e., there would be an increase in internal energy. Due to this, there will be an increase in temperature.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

JEE Atomic Structure and Chemical Bonding important Concepts and Tips

JEE Amino Acids and Peptides Important Concepts and Tips for Exam Preparation

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

Chemical Properties of Hydrogen - Important Concepts for JEE Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

Atomic Structure - Electrons, Protons, Neutrons and Atomic Models

Displacement-Time Graph and Velocity-Time Graph for JEE

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Learn About Angle Of Deviation In Prism: JEE Main Physics 2025

Types of Solutions

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

NCERT Solutions for Class 11 Chemistry In Hindi Chapter 1 Some Basic Concepts of Chemistry

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

JEE Advanced Weightage 2025 Chapter-Wise for Physics, Maths and Chemistry

Degree of Dissociation and Its Formula With Solved Example for JEE

NCERT Solutions for Class 11 Chemistry Chapter 7 Redox Reaction
