isothermische

Isothermische refers to a process or condition where the temperature remains constant. In thermodynamics, an isothermal process is one that occurs at a fixed temperature. This means that any heat exchanged with the surroundings is precisely balanced by the work done by or on the system, or by changes in internal energy that do not affect temperature.

For an ideal gas, an isothermal expansion or compression involves the gas doing work or having work done on it while absorbing or releasing heat such that its temperature does not change. The relationship between pressure and volume during an isothermal process for an ideal gas is described by Boyle's Law, which states that the product of pressure and volume is constant (PV = k) if the temperature and number of moles are held constant.

The concept of isotherms is also used in physical chemistry, particularly in adsorption studies. An adsorption isotherm is a graph that relates the amount of adsorbate adsorbed onto a solid surface to the pressure of the adsorbate at a constant temperature. Different shapes of adsorption isotherms, such as Langmuir or Freundlich isotherms, provide information about the nature of the interaction between the adsorbate and the adsorbent.

In broader scientific contexts, "isothermische" can simply denote a line or surface connecting points of equal temperature on a map or diagram, illustrating temperature distribution. This is common in meteorology, geology, and engineering to visualize thermal patterns.