activation energy

Also found in: Thesaurus, Medical, Acronyms, Encyclopedia, Wikipedia.

ac·ti·va·tion energy

The least amount of energy needed for a chemical reaction to occur. For example, striking a match on the side of a matchbox provides the activation energy, in the form of heat, necessary for the chemicals in the match to catch fire.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.activation energy - the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur; "catalysts are said to reduce the energy of activation during the transition phase of a reaction"
energy, free energy - (physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs; "energy can take a wide variety of forms"
aktivacijska energija
References in periodicals archive ?
As shown in Figure 4c, in the whole co-combustion process of the samples, the free activation energy curves show a declining trend with increasing CS in the blend.
The correlation between reaction rate constants and activation energy can be obtained using Arrhenius equation.
Since the activation energy of the second substitution is lower than that of the first, [DELTA][DELTA]E = -11.
a] is the activation energy for the moisture diffusion (kJ/mol), R is the ideal gas constant (8.
The activation energy for the water diffusion of corn ears during the drying process, obtained by the variation of the drying constant with temperature, was 17,644.
Figure 1a shows that similar behaviour of the knee point can be observed by the increase of the temperature, because the activation energy decreases with the rise of the temperature.
Diffusion coefficient obtained from the measured values of thickness IMF used to calculate the activation energy.
4] is expected to be of lower activation energy than that for 3-fsa.
The electrical properties such as sheet resistance, dc resistivity, and dark conductivity activation energy were measured by two probe method after gold coating for ohmic contacts of the films.
They noted that the activation energy of a thermal event can be directly determined from a series of TG runs performed at different rates.