Clausius ' PhD thesis concerning the refraction of light proposed that we see a blue sky during the day, and various shades of red at sunrise and sunset ( among other phenomena ) due to reflection and refraction of light.

Rudolf Clausius ' 1857 treatise entitled Über die Art der Bewegung, welche wir Wärme nennen ( On the Kind of Motion which we Call Heat ).< ref > Van der Waals, Johannes, D. ( 1910 ).

William Thomson ( Lord Kelvin ) amalgamated all of these laws into the laws of thermodynamics, which aided in the rapid development of explanations of chemical processes by Rudolf Clausius, Josiah Willard Gibbs, and Walther Nernst.

* 1857 – Clausius gives a modern and compelling account of the kinetic theory of gases in his On the nature of motion called heat

Building on the work of Clausius, between the years 1873-76 the American mathematical physicist Willard Gibbs published a series of three papers, the most famous one being the paper On the Equilibrium of Heterogeneous Substances.

In the diagram, the “ working body ” ( system ), a term introduced by Clausius in 1850, can be any fluid or vapor body through which heat Q can be introduced or transmitted to produce work.

Through the efforts of Clausius and Kelvin, it is now known that the maximum work that can be done is the product of the Carnot efficiency and the heat absorbed at the hot reservoir:

Since the latter is valid over the entire cycle, this gave Clausius the hint that at each stage of the cycle, work and heat would not be equal, but rather their difference would be a state function that would vanish upon completion of the cycle.

Then Clausius asked what would happen if there would be less work done than that predicted by Carnot's principle.

The German scientist Rudolf Clausius laid the foundation for the second law of thermodynamics in 1850 by examining the relation between heat transfer and work.

This sign convention is implicit in Clausius ' statement of the law given above, and is consistent with the use of thermodynamics to study heat engines which provide useful work, which is regarded as positive.

That very important state variable was first recognized and denoted by Clausius in 1850, but he did not then name it, and he defined it in terms not only of work but also of heat transfer in the same process.

These foundations enabled him to make substantive extensions of Clausius ' work, including the formula, now known as the Clausius – Clapeyron relation, which characterises the phase transition between two phases of matter.

Rudolf Clausius recognized the presence of a proportionality constant in Kelvin's analysis and gave it the name entropy in 1865 from the Greek for " transformation " because it describes the quantity of energy lost during transformation from heat to work.

Ice melting in a warm room is a common Entropy # Ice melting example | example of increasing entropy, described in 1862 by Rudolf Clausius as an increase in the disgregation of the water molecules in ice: order leading to disorder

In 1859, after reading a paper on the diffusion of molecules by Rudolf Clausius, Scottish physicist James Clerk Maxwell formulated the Maxwell distribution of molecular velocities, which gave the proportion of molecules having a certain velocity in a specific range.

* 1862 – " Disgregation ," a precursor of entropy, was defined in 1862 by Rudolf Clausius as the magnitude of the degree of separation of molecules of a body

Gibbs ’ collection of papers provided the first unified body of thermodynamic theorems from the principles developed by others, such as Clausius and Sadi Carnot.

Clausius originally called this the “ transformation content ” of the body, and then later changed the name to entropy.

His formulation of the second law, which was published in German in 1854, is known as the Clausius statement: " Heat can never pass from a colder to a warmer body without some other change, connected therewith, occurring at the same time.

Simply, Clausius states that it is impossible for a system to transfer heat from a cooler body to a hotter body.

Thus a violation of the Kelvin statement implies a violation of the Clausius statement, i. e. the Clausius statement implies the Kelvin statement.

In 1865, the German physicist Rudolf Clausius, in his Mechanical Theory of Heat, suggested that the principles of thermochemistry, e. g. the heat evolved in combustion reactions, could be applied to the principles of thermodynamics.

The Carnot engine model was graphically expanded upon by Benoît Paul Émile Clapeyron in 1834 and mathematically elaborated upon by Rudolf Clausius in 1857 and 66 from which the concept of entropy emerged.

The classical rule, recognized by Clausius and by Kelvin, is that the pressure exerted by the calorimetric material is fully and rapidly determined solely by its temperature and volume ; this rule is for changes that do not involve phase change, such as melting of ice.

It also led to a mathematical formulation of the concept of entropy by Clausius and to the introduction of laws of radiant energy by Jožef Stefan.

The thermodynamic definition was developed in the early 1850s by Rudolf Clausius and essentially describes how to measure the entropy of an isolated system in thermodynamic equilibrium.

Clausius called this state function entropy.

The word enthalpy is often incorrectly attributed to Benoit Paul Émile Clapeyron and Rudolf Clausius through the 1850 publication of their Clausius-Clapeyron relation.

* 1822 – Rudolf Clausius, German physicist ( d. 1888 )

Hence, the foundations of statistical thermodynamics were laid down in the late 1800s by those such as Maxwell, Boltzmann, Max Planck, Clausius, and Josiah Willard Gibbs who began to apply statistical and quantum atomic theory to ideal gas bodies.

The schools with the most-lasting effect in founding the modern versions of thermodynamics are the Berlin school, particularly as established in Rudolf Clausius ’ s 1865 textbook The Mechanical Theory of Heat, the Vienna school, with the statistical mechanics of Ludwig Boltzmann, and the Gibbsian school at Yale University, American engineer Willard Gibbs ' 1876 On the Equilibrium of Heterogeneous Substances launching chemical thermodynamics.

The foundations of statistical thermodynamics were set out by physicists such as James Clerk Maxwell, Ludwig Boltzmann, Max Planck, Rudolf Clausius and J. Willard Gibbs.

The word " virial " derives from vis, the Latin word for " force " or " energy ", and was given its technical definition by Rudolf Clausius in 1870.

In 1870, Rudolf Clausius delivered the lecture " On a Mechanical Theorem Applicable to Heat " to the Association for Natural and Medical Sciences of the Lower Rhine, following a 20 year study of thermodynamics.

* August 24 – Rudolf Clausius, German physicist, contributor to thermodynamics ( b. 1822 )

* January 2 – Rudolf Clausius, German physicist ( d. 1888 )

The Clausius – Clapeyron equation for water vapor in typical atmospheric conditions is

The term entropy was coined in 1865 by Rudolf Clausius based on the Greek εντροπία, a turning toward, from εν-( in ) and τροπή ( turn, conversion ).

Rudolf Clausius, with his kinetic theory on gases, gave another confirmation of Avogadro's Law.

In his 1851 paper, Thomson was willing to go no further than a compromise and declared " the whole theory of the motive power of heat is founded on ... two ... propositions, due respectively to Joule, and to Carnot and Clausius ".

Though in 1847 he published a paper in Liebig's Annalen der Chemie on the ' Mercaptan of Selenium ,' his mind was busy with the new ideas upon the nature of heat which were promulgated by Carnot, Clapeyron, Joule, Clausius, Mayer, Thomson, and Rankine.

Applying Clausius inequality on this loop,

* The crater Clausius on the Moon is named in his honor.

* Rudolf Clausius publishes his paper on the mechanical theory of heat, which first states the basic ideas of the second law of thermodynamics.

The idea of heat death was first proposed in loose terms beginning in 1851 by William Thomson, 1st Baron Kelvin, who theorized further on the mechanical energy loss views of Sadi Carnot ( 1824 ), James Joule ( 1843 ), and Rudolf Clausius ( 1850 ).

Callisto pontificates on the discoveries of the Laws of Thermodynamics, Clausius ' theorem, and Gibbs and Boltzmann, finally deciding that entropy is an adequate metaphor to apply to American consumerist society, " a similar tendency from the least to the most probable, from differentiation to sameness, from ordered individuality to a kind of chaos.

* Daub, E. E. ( 1970 ) " Waterston, Rankine and Clausius on the kinetic theory of gases ", Isis vol.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Clausius.

This theory, which was developed mainly between 1892 and 1906 by Lorentz and Poincaré, was based on the aether theory of Augustin-Jean Fresnel, Maxwell's equations and the electron theory of Rudolf Clausius.