Why is thermodynamics so important in chemistry

What is thermodynamics?

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I. Basics of thermodynamics

From the lexicon:

Ther | mo | dy | na | mik: [Greek thermos (warm, hot) + dynamics]: Theoretical theory of heat that deals with the relationships between heat and force or particle movements and with the phenomena caused by heat.


Thermodynamics is a branch of so-called physical chemistry. Its roots are mainly in the 18th and 19th centuries, with the scientists who dealt with states of equilibrium. This gave rise to so-called classical thermodynamics, which deals with changes in equilibrium in so-called closed systems, as well as infinitely slow processes. The time does not appear as a quantity here.
Classical thermodynamics separates the reversible processes, those in which the entropy does not change, from the irreversible ones, in which the entropy increases.
The so-called main clauses are the cornerstones of classical thermodynamics.
The more recently developed "Thermodynamics of irreversible processes" on the other hand, deals with states that are not in equilibrium and with processes that run at a finite speed, i.e. that end at some point. In addition, one looks at open systems instead of closed ones and time is an important variable.

Thermodynamics describes the states between systems with regard to temperature, pressure and volume changes and the relationships between these three variables.
Change one or more of these variables and see how the system reacts. By evaluating these considerations, so-called equations of state can be set up that describe the relationships found between the variables.
Furthermore, thermodynamics deals with the conversion of heat into other forms of energy (such as electrical energy, work, or light energy), as well as the reverse process. It has already been confirmed by numerous experiments that these energies can be converted into one another.
Thermochemistry also deals with the relationships between thermal and chemical energies. Chemical reactions and the associated energy and material conversions are examined. The energy (e.g. in the form of light) can be emitted or absorbed by the system. If, for example, heat is released, this reaction is called exothermic (see enthalpy). However, if it needs heat in order to be able to run off at all, thus absorbing energy, the reaction is called endothermic (see enthalpy). The heat effects that occur in chemical reactions are often more important than the reaction products, e.g. when burning coal, gas or oil for heating.

Significance for chemistry:

Chemistry as a science has actually only developed into an exact natural science through the precise investigation of physical quantities. As a result, the sub-area, physical chemistry, was formed. They can be used to explain and describe chemical processes and reactions more precisely. Thermodynamics is part of it.

What is thermodynamics?
History of Thermodynamics

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