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  2. Ammonium nitrate - Wikipedia

    en.wikipedia.org/wiki/Ammonium_nitrate

    Ammonium nitrate is a chemical compound with the formula NH 4 NO 3.It is a white crystalline salt consisting of ions of ammonium and nitrate.It is highly soluble in water and hygroscopic as a solid, but does not form hydrates.

  3. Enthalpy change of solution - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_change_of_solution

    The energy change can be regarded as being made up of three parts: the endothermic breaking of bonds within the solute and within the solvent, and the formation of attractions between the solute and the solvent. An ideal solution has a null enthalpy of mixing.

  4. Thermochemical equation - Wikipedia

    en.wikipedia.org/wiki/Thermochemical_equation

    In thermochemistry, a thermochemical equation is a balanced chemical equation that represents the energy changes from a system to its surroundings.One such equation involves the enthalpy change, which is denoted with In variable form, a thermochemical equation would appear similar to the following:

  5. 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

  6. Energy profile (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Energy_profile_(chemistry)

    The ∆G° can be written as a function of change in enthalpy (∆H°) and change in entropy (∆S°) as ∆G°= ∆H° – T∆S°. Practically, enthalpies, not free energy, are used to determine whether a reaction is favorable or unfavorable, because ∆ H ° is easier to measure and T ∆ S ° is usually too small to be of any significance ...

  7. Thermochemistry - Wikipedia

    en.wikipedia.org/wiki/Thermochemistry

    Endothermic reactions absorb heat, while exothermic reactions release heat. Thermochemistry coalesces the concepts of thermodynamics with the concept of energy in the form of chemical bonds. Thermochemistry coalesces the concepts of thermodynamics with the concept of energy in the form of chemical bonds.

  8. Enthalpy of mixing - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_of_mixing

    In thermodynamics, the enthalpy of mixing (also heat of mixing and excess enthalpy) is the enthalpy liberated or absorbed from a substance upon mixing. [1] When a substance or compound is combined with any other substance or compound, the enthalpy of mixing is the consequence of the new interactions between the two substances or compounds. [1]

  9. Standard enthalpy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_formation

    For many substances, the formation reaction may be considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction can then be analyzed by applying Hess' law, which states that the sum of the enthalpy changes for a number of individual reaction steps equals the enthalpy change of the overall reaction.