The term thermodynamics consists of two meaning thermo means heat and dynamics means movement. Thus thermodynamics can be defined as the branch of physical chemistry which deals with the study of different forms of energy and the quantitative relationship between them. In thermodynamics, heat either flow from surrounding to system or from system to surrounding. For example: When fuel burns, the heat flows from the surrounding to the system. In melting of ice, heat flows into the system from the surrounding.
Some thermodynamic terms:
In order to study the thermodynamic law, it is important to understand the certain terms that are often used in thermodynamics. They are as follows:
1. System: System is the part of the universe which is under thermodynamic study. It is the definite part while the surrounding is considered as unlimited. Examples:
- Ice in a beaker is called system while other part of universe is called surrounding.
- Chemical in a test tube is called system and other part of the universe is called surrounding.
2. Boundary: Boundary is the line or space that separates the system from the surrounding. Boundary are of two types, real and imaginary.
3. Surrounding: The region outside the boundary is called surrounding.