- Basics of Thermodynamics and Laws of Thermodynamics.

 Fundamental Concept 

1.System: A system can be any object, region of space etc, selected for study and set apart 

(mentally) from everything else. Which then become surrounding. 

The system of interest in thermodynamics are finite and macroscopic rather than 

microscopic. The imaginary envelope which encloses a system and separated it from its 

surrounding is called the boundary of the system. 

 2. Isolated system :It can not exchange either matter or energy with the surroundings. 

If exchange of matter is allowed the system is said to be open; if only energy and not 

matter is closed (but not isolated). 

3. Thermodynamical state 

A thermodynamic state is a set of values of properties of a thermodynamic system that 

must be specified to reproduce the system. 

Thermodynamic state is the macroscopic condition of a thermodynamic system as 

described by its particular thermodynamic parameter. Such as temperature (T) pressure 

(P) volume (V) density ( ) ρ . 

4.State function state function also called “State variable” thermodynamic variables 

describe the momentary condition of thermodynamic system 

For a continuous process, such variable are exact different also fully determined by their 

initial and final thermodynamic states. 

Example includes entropy, pressure, temperature, volume, etc. 

5. Intensive and extensive properties 

Intensive properties:-it is a physical property of a system that does not depend on the 

system size or the amount of material in system. It is scale invariant.