Caloric theory

Last updated April 15, 2024

The caloric theory is an obsolete scientific theory that heat consists of a self-repellent fluid called caloric that flows from hotter bodies to colder bodies. Caloric was also thought of as a weightless gas that could pass in and out of pores in solids and liquids. The "caloric theory" was superseded by the mid-19th century in favor of the mechanical theory of heat, but nevertheless persisted in some scientific literature—particularly in more popular treatments—until the end of the 19th century.^[1]

Early history

The world's first ice-calorimeter, used in the winter of 1782-83, by Antoine Lavoisier and Pierre-Simon Laplace, to determine the heat involved in various chemical changes; calculations which were based on Joseph Black's prior discovery of latent heat. These experiments mark the foundation of thermochemistry. Ice-calorimeter.jpg — The world's first **ice-calorimeter**, used in the winter of 1782–83, by Antoine Lavoisier and Pierre-Simon Laplace, to determine the heat involved in various chemical changes; calculations which were based on Joseph Black’s prior discovery of latent heat. These experiments mark the foundation of thermochemistry.

In the history of thermodynamics, the initial explanations of heat were thoroughly confused with explanations of combustion. After J. J. Becher and Georg Ernst Stahl introduced the phlogiston theory of combustion in the 17th century, phlogiston was thought to be the substance of heat.

There is one version of the caloric theory that was introduced by Antoine Lavoisier. Prior to Lavoisier's caloric theory, published references concerning heat and its existence, outside of being an agent for chemical reactions, were sparse only having been offered by Joseph Black in Rozier's Journal (1772) citing the melting temperature of ice.^[2] In response to Black, Lavoisier's private manuscripts revealed that he had encountered the same phenomena of a fixed melting point for ice and mentioned that he had already formulated an explanation which he had not published as of yet.^[3] Lavoisier developed the explanation of combustion in terms of oxygen in the 1770s. In his paper "Réflexions sur le phlogistique" (1783), Lavoisier argued that phlogiston theory was inconsistent with his experimental results, and proposed a 'subtle fluid' called caloric as the substance of heat.^[4] According to this theory, the quantity of this substance is constant throughout the universe,^{[ citation needed ]} and it flows from warmer to colder bodies. Indeed, Lavoisier was one of the first to use a calorimeter to measure the heat released during chemical reaction. Lavoisier presented the idea that caloric was a subtle fluid, obeying the common laws of matter, but attenuated to such a degree that it is capable of passing through dense matter without restraint; caloric's own material nature is evident when it is in abundance such as in the case of an explosion.^[2]

In the 1780s, Count Rumford believed that cold was a fluid, "frigoric" after the results of Pictet's experiment. Pierre Prévost argued that cold was simply a lack of caloric.

Since heat was a material substance in caloric theory, and therefore could neither be created nor destroyed, conservation of heat was a central assumption.^[5] Heat conduction was believed to have occurred as a result of the affinity between caloric and matter thus the less caloric a substance possessed, thereby being colder, attracted excess caloric from nearby atoms until a caloric, and temperature, equilibrium was reached.^[6]

Chemists of the time believed in the self-repulsion of heat particles as a fundamental force thereby making the great fluid elasticity of caloric, which does not create a repulsive force, an anomalous property which Lavoisier could not explain to his detractors.^[7]

Radiation of heat was explained by Lavoisier to be concerned with the condition of the surface of a physical body rather than the material of which it was composed.^[6]^[8] Lavoisier described a poor radiator to be a substance with a polished or smooth surface as it possessed its molecules lying in a plane closely bound together thus creating a surface layer of caloric which insulated the release of the rest within.^[6] He described a great radiator to be a substance with a rough surface as only a small amount of molecules held caloric in within a given plane allowing for greater escape from within.^[6] Count Rumford would later cite this explanation of caloric movement as insufficient to explain the radiation of cold becoming a point of contention for the theory as a whole.^[6]

The introduction of the caloric theory was influenced by the experiments of Joseph Black related to the thermal properties of materials. Besides the caloric theory, another theory existed in the late eighteenth century that could explain the phenomenon of heat: the kinetic theory. The two theories were considered to be equivalent at the time, but kinetic theory was the more modern one, as it used a few ideas from atomic theory and could explain both combustion and calorimetry. Caloric theory's inability to explain evaporation and sublimation further led to the rise of kinetic theory through the work of Count Rumford. Count Rumford observed solid mercury's tendency to melt under atmospheric conditions and thus proposed that the intensity of heat itself must stem from particle motion for such an event to occur where great heat was not expected to be.^[3]

Successes

Quite a number of successful explanations can be, and were, made from these hypotheses alone. We can explain the cooling of a cup of tea in room temperature: caloric is self-repelling, and thus slowly flows from regions dense in caloric (the hot water) to regions less dense in caloric (the cooler air in the room).

We can explain the expansion of air under heat: caloric is absorbed into the air, which increases its volume. If we say a little more about what happens to caloric during this absorption phenomenon, we can explain the radiation of heat, the state changes of matter under various temperatures, and deduce nearly all of the gas laws.

Sadi Carnot, who reasoned purely on the basis of the caloric theory, developed his principle of the Carnot cycle, which still forms the basis of heat engine theory. Carnot's analysis of energy flow in steam engines (1824) marks the beginning of ideas which led thirty years later to the recognition of the second law of thermodynamics.

Caloric was believed to be capable of entering chemical reactions as a substituent inciting corresponding changes in the matter states of other substances.^[2] Lavoisier explained that the caloric quantity of a substance, and by extent the fluid elasticity of caloric, directly determined the state of the substance.^[9] Thus, changes in state were a central aspect of a chemical process and essential for a reaction where the substituents undergo changes in temperature.^[9] Changes of state had gone virtually ignored by previous chemists making the caloric theory the inception point for this class of phenomena as a subject of interest under scientific inquiry.^[2]

However, one of the greatest apparent confirmations of the caloric theory was Pierre-Simon Laplace's theoretical correction of Sir Isaac Newton’s calculation of the speed of sound. Newton had assumed an isothermal process, while Laplace, a calorist, treated it as adiabatic.^[10] This addition not only substantially corrected the theoretical prediction of the speed of sound, but also continued to make even more accurate predictions for almost a century afterward, even as measurements became more precise.

Later developments

In 1798, Count Rumford published An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction , a report on his investigation of the heat produced while manufacturing cannons. He had found that boring a cannon repeatedly does not result in a loss of its ability to produce heat, and therefore no loss of caloric. This suggested that caloric could not be a conserved "substance", though the experimental uncertainties in his experiment were widely debated.

His results were not seen as a "threat" to caloric theory at the time, as this theory was considered to be equivalent to the alternative kinetic theory.^[11] In fact, to some of his contemporaries, the results added to the understanding of caloric theory.

Rumford's experiment inspired the work of James Prescott Joule and others towards the middle of the 19th century. In 1850, Rudolf Clausius published a paper showing that the two theories were indeed compatible, as long as the calorists' principle of the conservation of heat was replaced by a principle of conservation of energy. Although compatible however, the theories differ significantly in their implications. In modern thermodynamics, heat is usually a transfer of kinetic energy of particles (atoms, molecules) from a hotter to a colder substance.

In later combination with the law of energy conservation, the caloric theory still provides a valuable analogy for some aspects of heat, for example, the emergence of Laplace's equation and Poisson's equation in the problems of spatial distribution of heat and temperature.^{[ citation needed ]}

Notes

↑ The 1880 edition of A Guide to the Scientific Knowledge of Things Familiar, a 19th century educational science book, explained heat transfer in terms of the flow of caloric.
1 2 3 4 Morris, Robert J. (1972). "Lavoisier and the Caloric Theory". The British Journal for the History of Science. 6 (1): 1–38. doi:10.1017/S000708740001195X. ISSN 0007-0874. JSTOR 4025261. S2CID 45598864.
1 2 Guerlac, Henry (15 April 2019). Lavoisier-the Crucial Year : the Background and Origin of His First Experiments on Combustion in 1772. Cornell University Press. ISBN 978-1-5017-4664-2. OCLC 1138503811.
↑ Nicholas W. Best, Lavoisier's 'Reflections on Phlogiston' II: On the Nature of Heat, Foundations of Chemistry , 2016, 18, 3–13. In this early work, Lavoisier calls it “igneous fluid”. The term “caloric” was not coined until 1787, when Louis-Bernard Guyton de Morveau, used calorique in a work he co-edited with Lavoisier ("Mémoire sur le développement des principes de la nomenclature méthodique" in Guyton de Morveau, L.-B., Lavoisier, A.-L., Bertholet, C.-L., Fourcroy, A.-F. (eds.) Méthode de nomenclature chimique, pp. 26–74. Cuchet, Paris). The word “caloric” was first used in English in a translation of Guyton's essay by James St John ("A memoir to explain the principles of the methodical nomenclature" in Method of Chymical Nomenclature, Kearsley, London (1788), pp. 19–50, at p. 22).
↑ See, for example, Carnot, Sadi (1824). Réflexions sur la Puissance Motrice du Feu.
1 2 3 4 5 Brown, Sanborn C. (1967), "The Caloric Theory", Men of Physics: Benjamin Thompson – Count Rumford, Elsevier, pp. 16–24, doi:10.1016/b978-0-08-012179-6.50008-3, ISBN 9780080121796 , retrieved 2021-12-03
↑ Sage, Balthazar Georges. Mémoires de chimie. OCLC 1013352513.
↑ Brown, Sanborn C. (1967), "The Caloric Theory", Men of Physics: Benjamin Thompson – Count Rumford, Elsevier, pp. 16–24, doi:10.1016/b978-0-08-012179-6.50008-3, ISBN 9780080121796 , retrieved 2021-12-03
1 2 Khalal, A; Khatib, D; Jannot, B (1999). "Etude theorique de la dynamique du réseau de batio en phase quadratique". Annales de Chimie: Science des Matériaux. 24 (7): 471–480. doi:10.1016/s0151-9107(00)88439-1. ISSN 0151-9107.
↑ Psillos, Stathis (1999). Scientific Realism: How Science Tracks Truth. Routledge. p. 115. ISBN 978-0-203-97964-8.
↑ See for example Lavoisier, A.-L. de (1783). Mémoire sur la chaleur, lu à l'Académie royale des sciences, le 28 juin 1783, par MM. Lavoisier et de La Place.

Related Research Articles

Antoine-Laurent de Lavoisier, also Antoine Lavoisier after the French Revolution, was a French nobleman and chemist who was central to the 18th-century chemical revolution and who had a large influence on both the history of chemistry and the history of biology.

<span class="mw-page-title-main">Carnot heat engine</span> Theoretical engine

A Carnot heat engine is a theoretical heat engine that operates on the Carnot cycle. The basic model for this engine was developed by Nicolas Léonard Sadi Carnot in 1824. The Carnot engine model was graphically expanded by Benoît Paul Émile Clapeyron in 1834 and mathematically explored by Rudolf Clausius in 1857, work that led to the fundamental thermodynamic concept of entropy. The Carnot engine is the most efficient heat engine which is theoretically possible. The efficiency depends only upon the absolute temperatures of the hot and cold heat reservoirs between which it operates.

A heat engine is a system that converts heat to usable energy, particularly mechanical energy, which can then be used to do mechanical work. While originally conceived in the context of mechanical energy, the concept of the heat engine has been applied to various other kinds of energy, particularly electrical, since at least the late 19th century. The heat engine does this by bringing a working substance from a higher state temperature to a lower state temperature. A heat source generates thermal energy that brings the working substance to the higher temperature state. The working substance generates work in the working body of the engine while transferring heat to the colder sink until it reaches a lower temperature state. During this process some of the thermal energy is converted into work by exploiting the properties of the working substance. The working substance can be any system with a non-zero heat capacity, but it usually is a gas or liquid. During this process, some heat is normally lost to the surroundings and is not converted to work. Also, some energy is unusable because of friction and drag.

<span class="mw-page-title-main">Phlogiston theory</span> Superseded theory of combustion

The phlogiston theory, a superseded scientific theory, postulated the existence of a fire-like element dubbed phlogiston contained within combustible bodies and released during combustion. The name comes from the Ancient Greek φλογιστόνphlogistón, from φλόξphlóx (flame). The idea of a phlogistic substance was first proposed in 1667 by Johann Joachim Becher and later put together more formally in 1703 by Georg Ernst Stahl. Phlogiston theory attempted to explain chemical processes such as combustion and rusting, now collectively known as oxidation. The theory was challenged by the concomitant weight increase and was abandoned before the end of the 18th century following experiments by Antoine Lavoisier in the 1770s and by other scientists. Phlogiston theory led to experiments that ultimately resulted in the identification and naming (1777) of oxygen by Joseph Priestley.

Nicolas Léonard Sadi Carnot was a French mechanical engineer in the French Army, military scientist and physicist, often described as the "father of thermodynamics". He published only one book, the Reflections on the Motive Power of Fire, in which he expressed the first successful theory of the maximum efficiency of heat engines and laid the foundations of the new discipline: thermodynamics. Carnot's work attracted little attention during his lifetime, but it was later used by Rudolf Clausius and Lord Kelvin to formalize the second law of thermodynamics and define the concept of entropy. Driven by purely technical concerns, such as improving the performance of the steam engine, Sadi Carnot's theoretical work laid important foundations for modern science as well as technologies such as the automobile and jet engine.

In thermodynamics, the thermodynamic free energy is one of the state functions of a thermodynamic system. The change in the free energy is the maximum amount of work that the system can perform in a process at constant temperature, and its sign indicates whether the process is thermodynamically favorable or forbidden. Since free energy usually contains potential energy, it is not absolute but depends on the choice of a zero point. Therefore, only relative free energy values, or changes in free energy, are physically meaningful.

A timeline of events in the history of thermodynamics.

The law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. In the case of a closed system the principle says that the total amount of energy within the system can only be changed through energy entering or leaving the system. Energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another. For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes. If one adds up all forms of energy that were released in the explosion, such as the kinetic energy and potential energy of the pieces, as well as heat and sound, one will get the exact decrease of chemical energy in the combustion of the dynamite.

James Prescott Joule was an English physicist, mathematician and brewer, born in Salford, Lancashire. Joule studied the nature of heat, and discovered its relationship to mechanical work. This led to the law of conservation of energy, which in turn led to the development of the first law of thermodynamics. The SI derived unit of energy, the joule, is named after him.

Sir Benjamin Thompson, Count Rumford, FRS was a British physicist, born in Colonial Massachusetts, and inventor whose challenges to established physical theory were part of the 19th-century revolution in thermodynamics. He served as lieutenant-colonel of the King's American Dragoons, part of the British Loyalist forces, during the American Revolutionary War. After the end of the war he moved to London, where his administrative talents were recognized when he was appointed a full colonel, and in 1784 he received a knighthood from King George III. A prolific designer, Thompson also drew designs for warships. He later moved to Bavaria and entered government service there, being appointed Bavarian Army Minister and re-organizing the army, and, in 1792, was made a Count of the Holy Roman Empire.

This list catalogs well-accepted theories in science and pre-scientific natural philosophy and natural history which have since been superseded by scientific theories. Many discarded explanations were once supported by a scientific consensus, but replaced after more empirical information became available that identified flaws and prompted new theories which better explain the available data. Pre-modern explanations originated before the scientific method, with varying degrees of empirical support.

Calcination is thermal treatment of a solid chemical compound (e.g. mixed carbonate ores) whereby the compound is raised to high temperature without melting under restricted supply of ambient oxygen (i.e. gaseous O₂ fraction of air), generally for the purpose of removing impurities or volatile substances and/or to incur thermal decomposition.

"An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction" is a scientific paper by Benjamin Thompson, Count Rumford, which was published in the Philosophical Transactions of the Royal Society in 1798. The paper provided a substantial challenge to established theories of heat, and began the 19th century revolution in thermodynamics.

In the history of science, the mechanical equivalent of heat states that motion and heat are mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat, provided the work done is totally converted to heat energy. The mechanical equivalent of heat was a concept that had an important part in the development and acceptance of the conservation of energy and the establishment of the science of thermodynamics in the 19th century. Its independent and simultaneous discovery by James Prescott Joule and by Julius Robert von Mayer led to a priority dispute.

<span class="mw-page-title-main">History of thermodynamics</span>

The history of thermodynamics is a fundamental strand in the history of physics, the history of chemistry, and the history of science in general. Owing in the relevance of thermodynamics in much of science and technology, its history is finely woven with the developments of classical mechanics, quantum mechanics, magnetism, and chemical kinetics, to more distant applied fields such as meteorology, information theory, and biology (physiology), and to technological developments such as the steam engine, internal combustion engine, cryogenics and electricity generation. The development of thermodynamics both drove and was driven by atomic theory. It also, albeit in a subtle manner, motivated new directions in probability and statistics; see, for example, the timeline of thermodynamics.

<span class="mw-page-title-main">Chemical revolution</span> Reformulation of chemistry in the 17th and 18th centuries

In the history of chemistry, the chemical revolution, also called the first chemical revolution, was the reformulation of chemistry during the seventeenth and eighteenth centuries, which culminated in the law of conservation of mass and the oxygen theory of combustion.

Atmospheric thermodynamics is the study of heat-to-work transformations that take place in the Earth's atmosphere and manifest as weather or climate. Atmospheric thermodynamics use the laws of classical thermodynamics, to describe and explain such phenomena as the properties of moist air, the formation of clouds, atmospheric convection, boundary layer meteorology, and vertical instabilities in the atmosphere. Atmospheric thermodynamic diagrams are used as tools in the forecasting of storm development. Atmospheric thermodynamics forms a basis for cloud microphysics and convection parameterizations used in numerical weather models and is used in many climate considerations, including convective-equilibrium climate models.

Marie-Anne Pierrette Paulze Lavoisier, later Countess von Rumford, was a French chemist and noblewoman. Madame Lavoisier's first husband was the chemist and nobleman Antoine Lavoisier. She acted as his laboratory companion, using her linguistic skills to write up his work and bring it to an international audience. She also played a pivotal role in the translation of several scientific works, and was instrumental to the standardization of the scientific method.

In thermodynamics, heat is the thermal energy transferred between systems due to a temperature difference. In colloquial use, heat sometimes refers to thermal energy itself. Thermal energy is the kinetic energy of vibrating and colliding atoms in a substance.

<span class="mw-page-title-main">Claudine Picardet</span> French chemist, mineralogist, meteorologist and translator

Claudine Picardet was a chemist, mineralogist, meteorologist and scientific translator. Among the French chemists of the late eighteenth century she stands out for her extensive translations of scientific literature from Swedish, English, German and Italian to French. She translated three books and thousands of pages of scientific papers, which were published as well as circulated in manuscript form. She hosted renowned scientific and literary salons in Dijon and Paris, and was an active participant in the collection of meteorological data. She helped to establish Dijon and Paris as scientific centers, substantially contributing to the spread of scientific knowledge during a critical period in the chemical revolution.

References

Fox, R. (1971). The Caloric Theory of Gases. Clarendon Press: Oxford.
Chang, H.S. (2003). "Preservative realism and its discontents: Revisiting caloric" (PDF). Philosophy of Science. 70 (5): 902–912. doi:10.1086/377376. S2CID 40143106.
Mendosa, E. (February 1961). "A sketch for a history of early thermodynamics". Physics Today. 14 (2): 32–42. Bibcode:1961PhT....14b..32M. doi:10.1063/1.3057388.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[1] The 1880 edition of A Guide to the Scientific Knowledge of Things Familiar, a 19th century educational science book, explained heat transfer in terms of the flow of caloric.

[:0-2] 1 2 3 4 Morris, Robert J. (1972). "Lavoisier and the Caloric Theory". The British Journal for the History of Science. 6 (1): 1–38. doi:10.1017/S000708740001195X. ISSN 0007-0874. JSTOR 4025261. S2CID 45598864.

[:3-3] 1 2 Guerlac, Henry (15 April 2019). Lavoisier-the Crucial Year : the Background and Origin of His First Experiments on Combustion in 1772. Cornell University Press. ISBN 978-1-5017-4664-2. OCLC 1138503811.

[4] Nicholas W. Best, Lavoisier's 'Reflections on Phlogiston' II: On the Nature of Heat, Foundations of Chemistry , 2016, 18, 3–13. In this early work, Lavoisier calls it “igneous fluid”. The term “caloric” was not coined until 1787, when Louis-Bernard Guyton de Morveau, used calorique in a work he co-edited with Lavoisier ("Mémoire sur le développement des principes de la nomenclature méthodique" in Guyton de Morveau, L.-B., Lavoisier, A.-L., Bertholet, C.-L., Fourcroy, A.-F. (eds.) Méthode de nomenclature chimique, pp. 26–74. Cuchet, Paris). The word “caloric” was first used in English in a translation of Guyton's essay by James St John ("A memoir to explain the principles of the methodical nomenclature" in Method of Chymical Nomenclature, Kearsley, London (1788), pp. 19–50, at p. 22).

[5] See, for example, Carnot, Sadi (1824). Réflexions sur la Puissance Motrice du Feu.

[:2-6] 1 2 3 4 5 Brown, Sanborn C. (1967), "The Caloric Theory", Men of Physics: Benjamin Thompson – Count Rumford, Elsevier, pp. 16–24, doi:10.1016/b978-0-08-012179-6.50008-3, ISBN 9780080121796 , retrieved 2021-12-03

[7] Sage, Balthazar Georges. Mémoires de chimie. OCLC 1013352513.

[8] Brown, Sanborn C. (1967), "The Caloric Theory", Men of Physics: Benjamin Thompson – Count Rumford, Elsevier, pp. 16–24, doi:10.1016/b978-0-08-012179-6.50008-3, ISBN 9780080121796 , retrieved 2021-12-03

[:1-9] 1 2 Khalal, A; Khatib, D; Jannot, B (1999). "Etude theorique de la dynamique du réseau de batio en phase quadratique". Annales de Chimie: Science des Matériaux. 24 (7): 471–480. doi:10.1016/s0151-9107(00)88439-1. ISSN 0151-9107.

[10] Psillos, Stathis (1999). Scientific Realism: How Science Tracks Truth. Routledge. p. 115. ISBN 978-0-203-97964-8.

[11] See for example Lavoisier, A.-L. de (1783). Mémoire sur la chaleur, lu à l'Académie royale des sciences, le 28 juin 1783, par MM. Lavoisier et de La Place.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]