Common terminologies used in thermodynamics

While learning thermodynamics we come across many terms , out of that some of then have been discussed here .

Let us start

🚩 System- 

Part of the universe which is under investigation, comes under system. 

🚩 Open System-

 A system which can exchange both energy and matter with its surroundings is called as an open system.

🚩 Closed System- 

A system which permits passage of energy but not mass, across its boundary, such system is called as closed system.

🚩 Isolated system- 

A system which can neither exchange energy nor matter with its surrounding is called as isolated system.

🚩 Surroundings- 

Part of the universe other than system, which can interact with it is called as surrounding.

🚩 Boundary- 

Anything which separates system from surrounding is called as a boundary. 

🚩 State variables- 

The variables which are required to be defined in order to define state of any system i.e. pressure, volume, mass, temperature, surface area, etc. are called as state variables.

🚩 State Functions-

 Property of system which depend only on the state of the system and not on the path. Example: Pressure, volume, temperature, internal energy, enthalpy, entropy etc. are all state functions. 

🚩 Intensive properties-

 Properties of a system which do not depend on mass of the system i.e. temperature, pressure, density, concentration are termed as intensive properties. 

🚩 Extensive properties-

 Properties of a system which depend on mass of the system i.e. volume, energy, enthalpy, entropy etc. are called as extensive properties.

🚩 Process- 

Path along which state of a system changes is termed as process. 

🚩 Isothermal process- 

Process which takes place at constant temperature is called as isothermal process.

🚩 Isobaric process- 

Process which takes place at constant pressure is called as isobaric process. 

🚩 Isochoric process-

 Process which takes place at constant volume is called as isochoric process.

🚩 Adiabatic process- 

Process during which transfer of heat cannot take place between system and surrounding is called as adiabatic process.

🚩 Cyclic process- 

Process in which system comes back to its initial state after undergoing series of changes is termed as a cyclic process. 

🚩 Reversible process- 

Process during which the system always departs infinitesimally from the state of equilibrium i.e. its direction can be reversed at any moment is called as reversible process. 

🚩 Irreversible Process- 

This type of process is fast and gets completed in a single step. This process cannot be reversed. All the natural processes are of this type.