As per the thermodynamic terminology, in the adiabatic process, there is no exchange of heat from the system to its surroundings neither during expansion nor during compression. Whereas in the isothermal process, the temperature remains constant throughout the work. This article will definitely help to understand the difference between isothermal and adiabatic process.
In thermodynamics, we study the systems and objects in relation to the measurement of their temperatures, motions, and other physical characteristics. This is applicable to anything from the single-celled organisms to the mechanical systems in the universe. Therefore we can see thermodynamics as the specific branch which deals with the relationships between heat energy and other forms of energy. It also describes the conversion of thermal energy into other forms of energy as well as their effects on the matter. In this regards two very important processes are there- The isothermal process and the Adiabatic Process.
What is Isothermal Process?
It is a thermodynamic process in which the temperature of a system remains constant with respect to time. The transfer of heat into or out of the system is happening at a very slow pace to maintain the thermal equilibrium. At a given constant temperature, the change of the substance, object, or even the system is the Isothermal Process.
If a system is in contact with an outside thermal reservoir, then, to maintain thermal equilibrium, the system tries to adjust itself with the reservoir’s temperature through heat exchange. Thus, for an isothermal process, the change in temperature will always be zero for an ideal system.
What is Adiabatic Process?
This is another type of phenomenon in thermodynamic, which is an adiabatic process. In the adiabatic process, no heat transfer occurs between the system and its surrounding. In such a type of process, the temperature of the system changes to maintain the heat constant.
Therefore, in the adiabatic process, the change in system occurs without the transfer of heat or a matter between a thermodynamic system and its surroundings. This adiabatic process may be either reversible or irreversible. Two essential conditions for the adiabatic process are-
- The system should be completely insulated from the surrounding.
- The process must occur quickly for getting a sufficient amount of time to transfer the heat.
Difference between Isothermal and Adiabatic process
|Definition||It is defined as one of the thermodynamic processes which occur at a constant temperature.||It is defined as one of the thermodynamic processes which occur without any heat transfer between the system and the surrounding|
|Heat transfer||It contains the transfer of heat.||It does not contain the transfer of heat.|
|Pressure vs volume||The pressure is more in comparison to volume.||The pressure is less in comparison to volume.|
|Temperature||The temperature remains constant in such a process.||Temperature changes due to variations in the internal system in such a process.|
|Heat||To maintain the temperature, heat can be added or released to the system.||No need to add or release the heat, constant temperature maintenance is not required here.|
|Rate of transformation||The transformation is slow in such a process.||The transformation is fast in such a process.|
After having the difference between the Isothermal and Adiabatic process. Let us have some examples.
Examples of Isothermal Process:
There are many instances, some are as follows:
- Changes of state or phase changes of different liquids during melting and evaporation processes.
- One industrial application of it is in the Carnot engine.
- A refrigerator is a good example of the isothermal process.
- One more example is the heat pump, useful to remove the heat from the house.
Examples of the adiabatic process:
There are many instances, some are as follows:
- In this process, gas compression is happening with the generation of heat. One such example will be the release of air from a pneumatic tire.
- Adiabatic Efficiency is applicable to devices like nozzles, compressors, and turbines.
- One popular example is the pendulum oscillating in a vertical plane.
- A quantum harmonic oscillator is another famous example of an adiabatic system.
- While putting the ice into the icebox, no heat will go out and no heat will come in. it is the adiabatic process.
FAQs about the isothermal and adiabatic process:
Q.1: How the heat content of the system will change at constant temperature?
Solution: To change the heat content, it is necessary to have the existence of a temperature gradient. It means the system will remain at constant temperature and still may reject or accept heat if the surrounding is at a different temperature.
Q.2: How the system temperature will change at constant heat content?
Solution: It is possible by the work done on the system and so, the temperature of the system will change even if there is no heat content added or removed from it. Temperature and heat both are different terms. Heat is the energy in transit, but the temperature is the property of a system like pressure and volume.