Profile
Settings
Refer your friends
Sign out
Thermodynamics, in its broadest sense, is concerned with the transfer of energy from one location to another and from one form to another. Heat is a type of energy that corresponds to a specific quantity of mechanical work, which is the central notion.
Thermodynamic Equilibrium
When no changes in macroscopic properties are detected, a system is considered to be in thermodynamic equilibrium. A system will be in thermodynamic equilibrium if the following conditions are met:
(i) Mechanical Equilibrium – without the presence of an unbalanced force both within the system and between it and its surroundings
(ii) Chemical balance – Any chemical reaction or substance transfer from one component of the system to another is absent.
iii) Thermal equilibrium- When a system is divided from its surroundings by a diathermic wall (diathermic means “allowing heat to circulate”), it is in thermal equilibrium.
The system cannot be in thermodynamic equilibrium if one of these conditions is not met.
Laws of Thermodynamics
Talking about the basic concepts of thermodynamics, you first need to understand the types of associated laws:
The zeroth law of thermodynamics applies. When the first two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with one another. This characteristic enables defining a temperature scale and utilising thermometers as a “third system” meaningful.
The first law of thermodynamics is sometimes known as the law of energy conservation. The difference between heat added to the system from its surroundings and work done by the system on its surroundings equals the change in a system’s internal energy.
The second law of thermodynamics describes how heat is transferred from one place to another. Heat does not naturally flow from a colder to a hotter region, or, to put it another way, heat at a particular temperature cannot be turned totally into work. As a result, the entropy of a closed system, or the amount of heat energy per unit of temperature, grows with time, eventually reaching a maximum value. As a result, all closed systems converge to a state of equilibrium where entropy is greatest and no energy is available to conduct beneficial work.
The Third Law of Thermodynamics is one of the most important laws of thermodynamics. The permeability of a crystalline sample of a substance in its most stable state decreases to zero as the temperature approaches absolute zero. This allows for the establishment of an absolute entropy scale, which statistically quantifies the degree of randomness or disorder in a system.
If physical traits and chemical compositions are consistent throughout a system, it is considered to be homogenous. A system, on the other hand, is heterogeneous if it consists of pieces with different physical and chemical properties. A system can be classified into three groups based on how matter and energy enter and exit it. There are three types of systems to choose from.
Basic Concepts of Thermodynamics
1.Open System: The term “open system” refers to a system that may exchange both matter and energy with its environment. As a result, in an open system, mass and energy can be transferred between the system and its surroundings. Because it gains and loses matter as well as energy, hot coffee in an open flask is an example of an open system.
2.Closed System: A closed system is one of the crucial fundamentals of thermodynamics that exchanges energy with its surroundings but does not exchange matter. The transmission of energy occurs across the closed system’s boundary, but the mass is not transferred. Refrigerators and gas compression in the piston-cylinder assembly are examples of closed systems. Coffee in a stainless flask is also an example of a closed system because energy can flow through the steel walls but not matter.
3.Isolated System: A system that is isolated from its surroundings is unable to exchange matter or energy. There is no such thing as a perfectly isolated system. An isolated system, on the other hand, is completely sealed to prevent matter entry or outflow while also being thermally insulated to prevent heat flow. It is thought that the cosmos is self-contained. Because it cannot gain or lose energy or matter, coffee in a vacuum flask is an example of an isolated system.
Conclusion
That’s a wrap to the fundamental concepts of thermodynamics!
Despite the fact that thermodynamics expanded fast in the nineteenth century in response to the need to increase the performance of steam engines, the rules of thermodynamics are applicable to all physical and biological systems due to their enormous universality. The laws of thermodynamics, in particular, provide a thorough account of all changes in a system’s energy state and its ability to perform positive work on its environments.
