enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Enthalpy of mixing - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_of_mixing

    Enthalpy of mixing can often be ignored in calculations for mixtures where other heat terms exist, or in cases where the mixture is ideal. [2] The sign convention is the same as for enthalpy of reaction: when the enthalpy of mixing is positive, mixing is endothermic, while negative enthalpy of mixing signifies exothermic mixing. In ideal ...

  3. Endothermic process - Wikipedia

    en.wikipedia.org/wiki/Endothermic_process

    An endothermic process is a chemical or physical process that absorbs heat from its surroundings. [1] In terms of thermodynamics, it is a thermodynamic process with an increase in the enthalpy H (or internal energy U) of the system. [2] In an endothermic process, the heat that a system absorbs is thermal energy transfer into the

  4. Enthalpy change of solution - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_change_of_solution

    The integral heat of dissolution is defined as a process of obtaining a certain amount of solution with a final concentration. The enthalpy change in this process, normalized by the mole number of solute, is evaluated as the molar integral heat of dissolution. Mathematically, the molar integral heat of dissolution is denoted as:

  5. Thermochemical equation - Wikipedia

    en.wikipedia.org/wiki/Thermochemical_equation

    , , and are the usual agents of a chemical equation with coefficients and is a positive or negative numerical value, which generally has units of kJ/mol. Another equation may include the symbol E {\displaystyle E} to denote energy; E {\displaystyle E} 's position determines whether the reaction is considered endothermic (energy-absorbing) or ...

  6. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    Van 't Hoff plot for an endothermic reaction. For an endothermic reaction, heat is absorbed, making the net enthalpy change positive. Thus, according to the definition of the slope: =, When the reaction is endothermic, Δ r H > 0 (and the gas constant R > 0), so

  7. Enthalpy - Wikipedia

    en.wikipedia.org/wiki/Enthalpy

    Enthalpy (/ ˈ ɛ n θ əl p i / ⓘ) is the sum of a thermodynamic system's internal energy and the product of its pressure and volume. [1] It is a state function in thermodynamics used in many measurements in chemical, biological, and physical systems at a constant external pressure, which is conveniently provided by the large ambient atmosphere.

  8. Thermal decomposition - Wikipedia

    en.wikipedia.org/wiki/Thermal_decomposition

    The reaction is usually endothermic as heat is required to break chemical bonds in the compound undergoing decomposition. If decomposition is sufficiently exothermic, a positive feedback loop is created producing thermal runaway and possibly an explosion or other chemical reaction. Thermal decomposition is a chemical reaction where heat is a ...

  9. Hess's law - Wikipedia

    en.wikipedia.org/wiki/Hess's_law

    The law states that the total enthalpy change during the complete course of a chemical reaction is independent of the sequence of steps taken. [2] [3] Hess's law is now understood as an expression of the fact that the enthalpy of a chemical process is independent of the path taken from the initial to the final state (i.e. enthalpy is a state ...