Thermodynamics topic for B.Sc first year

Thermodynamics. It covers the following topics:

1. The Surroundings and the System:

Defines the system as the part of the universe under study and the surroundings as everything else.
Explains that the system and surroundings interact through energy and matter exchange.
2. Types of Systems:

Discusses three types of systems: open, closed, and isolated.
Open systems exchange both matter and energy with the surroundings.
Closed systems exchange only energy with the surroundings.
Isolated systems do not exchange either matter or energy with the surroundings.
3. The State of the System:

Defines the state of a system as the condition of the system at a particular instant.
Explains that the state of a system is determined by its properties, such as temperature, pressure, and volume.
Introduces the concept of a macroscopic state, which is the overall state of a system as observed without considering the individual particles.
4. The Internal Energy of the System:

Defines the internal energy of a system as the total kinetic and potential energies of all the particles in the system.
Explains that internal energy is a state function, meaning it depends only on the current state of the system and not on the path taken to reach that state.  
5. The First Law of Thermodynamics:

States that the total energy of an isolated system is constant.
Introduces the concept of heat (Q) and work (W) as forms of energy transfer.
Mathematically expresses the first law as ΔU = Q - W, where ΔU is the change in internal energy.
6. Adiabatic Processes:

Defines an adiabatic process as one in which no heat is exchanged between the system and the surroundings.
Explains that in an adiabatic process, the change in internal energy is equal to the work done on or by the system.
7. Isothermal Processes:

Defines an isothermal process as one in which the temperature of the system remains constant.
Explains that in an isothermal process, the heat exchanged between the system and the surroundings is equal to the work done on or by the system.

1. UNIT : IV
THERMODYNAMICS
BY
BHANUDAS NARWADE
ASST.PROF.
DEGLOOR COLLEGE,DEGLOOR

2. Thermodynamics:
Thermodynamics:
Branch of science deals with interconversion between heat and different
forms of energy
Thermodynamic system: Definite quantity of matter bounded by closed
surface
Thermodynamic variables: composition , pressure, volume and temperature
Variables of state: composition , pressure, volume and temperature
For homogeneous system, composition is fixed
Three class of system: Open system-exchange of matter and energy with
surrounding

3. Thermodynamics:
Closed system: System only exchange only energy and not matter with
surrounding
Isolated system: Thermally insulated and no communication of heat or work
with surrounding
Heat: Energy in transits. If body is at constant temp., it has both mechanical
and thermal energy due to thermal agitation
Work done: work is done on body or by a body, depend on path of process
Internal energy: Energy contents of system. It is sum of KE ,PE and energy of
electrons and nuclie
KE is due to translational, rotational and vibrational motion of molecule
PE is isdue to intermolecular forces

4. FIRST LAW OF THERMODYNAMICS
Statement: ??????�=??????�+??????�
??????�is taken positive when heat is supplied to system and negative when heat
is removed from system
??????�is positive when work is done by the system in expansion and negative
when work is done on the system in compression
Significance:
Applicable to any system in which system undergoes physical or chemical
change
Introduces concept of internal energy
Provides determining change in internal energy

5. Thermodynamics
Specific heats of gas: Heat capacity per unit mass
Isothermal process: system perfectly conducting and constant temperature
Adiabatic process : No heat leaves or enter the system ??????�=0
Isochoric Process : volume constant no external work is done ??????�=0
Isobaric process: pressure remains constant heat absorbed at constant
pressure is equal to increase in enthalphy
Cyclic Process: ׯ??????�=ׯ??????�+ׯ??????�
System restore to initial state at the end of each cycle

6. Adiabatic Process:
During adiabatic process
Relation between pressure and volume ��
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Relation between temperature and volume ��
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= constant
Relation between pressure and temperature
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7. SECOND LAW OF THERMODYNAMICS

8. SECOND LAW OF THERMODYNAMICS

9. SECOND LAW OF THERMODYNAMICS

10. ENTROPY:
Q

11. Heat engines:
Carnot’s heat Engine:

12. Carnot’s cycle:
1Isothermal Expansion:
2Adiabatic expansion
3Isothermal compression
4Adiabatic compression

13. Carnot’s cycle:
1Isothermal Expansion:
Substance absorbs Q1amount of heat
from source and does work W1 is
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14. Carnot’s cycle:
2Adiabatic Expansion:
No transfer of heat
Temperature falls to T
2and does some
external work W
2
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15. Carnot’s cycle:
3Isothermal Compression:
Substance reject Q2 amount of heat
to sink at T2 ,Work W3 is done on
substance
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16. Carnot’s cycle:
4Adiabatic Compression:
No transfer of heat
Temperature rises to T
1and does
some external work W
4
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17. Carnot’s cycle:
Net heat absorbed by gas per cycle= Q1-Q2
Net work done per cycle W1+W2+W3+W4
=W1+W3
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18. Carnot’s Theorem:
Carnot’s cycle is perfect reversible works as heat
engine as well as refrigerator
Theorem:
Statement:1 No engine can be more efficient than
carnot’sreversible engine working between same
two temperatures
2 Efficiency of all reversible engine working between
same two temperature is same whatever may be
working substance

19. Thermodynamic relations:
Thermodynamic variables: Pressure temp, volume, internal energy and entropy
Maxwell’s thermodynamical relations:
Using first and second law of thermodynamic Maxwell derived six equations
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20. T Ds Equations:
The first T-ds equation is:
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Second T dSequation: ���=??????
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The Clausius-Clapeyron latent heat equation is
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