Search results
Results from the WOW.Com Content Network
In thermodynamics, an exothermic process (from Ancient Greek έξω (éxō) 'outward' and θερμικός (thermikós) 'thermal') [1] is a thermodynamic process or reaction that releases energy from the system to its surroundings, [2] usually in the form of heat, but also in a form of light (e.g. a spark, flame, or flash), electricity (e.g. a ...
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 ...
The reduction of iron (III) oxide by aluminium releases sufficient heat to yield molten iron. In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change Δ H ⚬ is negative." [1][2] Exothermic reactions usually release heat. The term is often confused with exergonic reaction, which IUPAC defines as ...
t. e. An endotherm (from Greek ἔνδον endon "within" and θέρμη thermē "heat") is an organism that maintains its body at a metabolically favorable temperature, largely by the use of heat released by its internal bodily functions instead of relying almost purely on ambient heat. Such internally generated heat is mainly an incidental ...
A thermochemical equation is a balanced stoichiometric chemical equation that represents the energy changes from a system to its surroundings. One such equation involves the enthalpy change, which is denoted with ΔH. In variable form, a thermochemical equation would appear similar to the following: A + B → C. ΔH = (±) #.
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 ...
This can be explained with reference to potential energy diagrams: Energy diagrams showing how to interpret Hammond's Postulate. In case (a), which is an exothermic reaction, the energy of the transition state is closer in energy to that of the reactant than that of the intermediate or the product.
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 ...