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  2. 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 and thermochemistry, 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 ...

  3. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    The Van 't Hoff equation relates the change in the equilibrium constant, Keq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, ΔrH⊖, for the process. The subscript means "reaction" and the superscript means "standard". It was proposed by Dutch chemist Jacobus Henricus van 't Hoff in 1884 in his book ...

  4. Energy profile (chemistry) - Wikipedia

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

    Energy profile (chemistry) In theoretical chemistry, an energy profile is a theoretical representation of a chemical reaction or process as a single energetic pathway as the reactants are transformed into products. This pathway runs along the reaction coordinate, which is a parametric curve that follows the pathway of the reaction and indicates ...

  5. Hess's law - Wikipedia

    en.wikipedia.org/wiki/Hess's_law

    Hess' law allows the enthalpy change (Δ H) for a reaction to be calculated even when it cannot be measured directly. This is accomplished by performing basic algebraic operations based on the chemical equations of reactions using previously determined values for the enthalpies of formation. Combination of chemical equations leads to a net or ...

  6. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    For example, in an exothermic reaction the transition state is closer in energy to the reactants than to the products. Therefore, the transition state will be more geometrically similar to the reactants than to the products. In contrast, however, in an endothermic reaction the transition state is closer in energy to the products than to the ...

  7. Thermal decomposition - Wikipedia

    en.wikipedia.org/wiki/Thermal_decomposition

    Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. The reaction is usually endothermic as heat is required to break chemical bonds in the compound undergoing decomposition.

  8. Thermochemistry - Wikipedia

    en.wikipedia.org/wiki/Thermochemistry

    Thermochemistry. Thermochemistry is the study of the heat energy which is associated with chemical reactions and/or phase changes such as melting and boiling. A reaction may release or absorb energy, and a phase change may do the same. Thermochemistry focuses on the energy exchange between a system and its surroundings in the form of heat.

  9. Chemical decomposition - Wikipedia

    en.wikipedia.org/wiki/Chemical_decomposition

    The reaction is written as: H 2 CO 3 → H 2 O + CO 2. Other carbonates will decompose when heated to produce their corresponding metal oxide and carbon dioxide. [5] The following equation is an example, where M represents the given metal: MCO 3 → MO + CO 2. A specific example is that involving calcium carbonate: CaCO 3 → CaO + CO 2