# Thermodynamics Class 11 Notes PDF

## Thermodynamics Class 11 Notes PDF Summary

Hello students, Today we are going to upload the Thermodynamics Class 11 Notes PDF to help students as well as tutors. Thermodynamics is essentially the study of the flow of energy. Its entire chapter is based on the mounting that there is transference and conversion of energy from one form to another. Since the measure of energy has to be about a specific system, class 11 Chemistry chapter 6 thermodynamics notes begin with elaborating various properties of a system.
The chapter on thermodynamics in CBSE class 11 Chemistry is quite exhaustive in its content. A student has to learn multiple topics under this chapter, along with the relevant mathematical sums. To fully grasp the chapter, the core concepts must be clear at the outset. Students, while preparing this lesson, can download the PDF of the notes.

### Detailed Table of the Chapter 6 Notes – Thermodynamics Class 11 Notes PDF

 1 Board CBSE 2 Textbook NCERT 3 Class Class 11 4 Subject Science Notes 5 Chapter Chemistry Chapter 6 6 Chapter Name Thermodynamics 7 Category CBSE Revision Notes

## Thermodynamics Class 11 Notes PDF – Short Notes

THermodynamics terminology:

• System:

A notable part of the universe that is kept under observation is known as the system.

• Surrounding:

The remaining part of the universe except for the system which isn’t kept under observation is known as surroundings.
In general, it can be stated as;
Universe = System + Surrounding

• Types of the system:
1. a) Open system –

The system where the flow of both, mass and heat energy takes place.
Example: Human body.

1. b) Closed system –

The system where the flow of heat energy takes place but has constant mass.
Example: Pressure cooker.

1. c) Isolated system –

The system where none of the flow takes place.
State of the system:
The state of the system can be defined and changed with respect to the changes in state variables i.e., P, V, T, and n. These variables define the conditions of the system and change in any one of them, will change the state of the system.
Properties of the system:

• Intensive properties –

Properties depend upon concentration and are independent of mass or the total number of particles in the system. They are pressure, refractive index, density, etc.

• Extensive properties –

Properties depend upon the mass or the total number of particles in the system. They are volume, total energy, etc.
State and path function:

• State function –

The function will be independent of the path followed but will depend upon the initial and final states while bringing up the changes in the system.
Example: internal energy, enthalpy, etc.

• Path function –

The function will depend upon the path followed while bringing up the changes in the system.
Example: work, heat, etc.

### Thermodynamics Class 11 Notes PDF – Mode of Energy Transport

Modes of energy transport:

• Heat –

The energy transferred due to temperature differences within the system and surroundings is known as heat (Q). When the system is heated, the kinetic energy of the molecules is being increased which then increases the internal energy.

• Work –

The energy spent to overcome the external forces acting upon the system is known as work (W). When a system expands, the internal energy is reduced. Whereas, on the contraction of the system the internal energy is increased.
Reversibility:
The process can change its direction by very small i.e., infinitesimal change in the system or surrounding; retracting its original path reaching the same initial state. In a process to follow reversibility, there must not be any dissipative forces and the system must be in Quasi-Static State.

• Quasi-static state –

Here, the system seems to be static at all time intervals but not actually in reality. The motion is so slow that the system seems to be in equilibrium with the surroundings.
Expansion work:
The work done due to changes in the volume of the system is known as expansion work. Note that, let it be expansion or compression, we take external pressure as the driving force.
Mathematically, it can be represented as;
W=−∫PexdVW=−∫PexdV
For reversible processes, external pressure is considered equal to the pressure of the gas. Thus,
W=−∫PgasdVW=−∫PgasdV
When a P – V graph is drawn, work done is represented as the area covered under it as shown;
Sign conventions:

• W –

Positive if the volume of the system is decreasing and negative when the volume of the system is increasing.

• ΔUΔU –

When the temperature of the system or product pressure or volume is reducing, it is negative; else is positive.

• Q –

This needs to be determined by the first law of thermodynamics.
Cyclic process:
A process that comes back to its original and initial state is known as a cyclic process. A closed graph determines this process and here, ΔU=0ΔU=0 and Qnet=−WnetQnet=−Wnet. 