Chemical Energy is a Form of _____ Energy

Energy released from chemical substances

Chemical energy
is the free energy of chemic substances that is released when they undergo a chemical reaction and transform into other substances. Some examples of storage media of chemical energy include batteries, nutrient, and gasoline. Breaking and making chemic bonds involves free energy, which may be either absorbed past or evolved from a chemical system.

Energy that can exist released or absorbed because of a reaction between chemical substances is equal to the difference between the energy content of the products and the reactants, if the initial and terminal temperature is the aforementioned. This alter in energy tin be estimated from the bail energies of the reactants and products. It tin besides be calculated from

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{\displaystyle \Delta {U_{f}^{\circ }}_{\mathrm {reactants} }}

, the internal energy of germination of the reactant molecules, and

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{\displaystyle \Delta {U_{f}^{\circ }}_{\mathrm {products} }}

, the internal energy of formation of the product molecules. The internal energy modify of a chemical process is equal to the estrus exchanged if it is measured under atmospheric condition of constant volume and equal initial and final temperature, every bit in a closed container such as a flop calorimeter. All the same, under atmospheric condition of constant pressure level, as in reactions in vessels open to the atmosphere, the measured heat change is non ever equal to the internal energy alter, because pressure-volume work also releases or absorbs energy. (The heat change at constant force per unit area is equal to the enthalpy change, in this example the enthalpy of reaction, if initial and final temperatures are equal).

A related term is the heat of combustion, which is the free energy released due to a combustion reaction and often applied in the study of fuels. Nutrient is similar to hydrocarbon and carbohydrate fuels, and when information technology is oxidized to carbon dioxide and water, the energy released is analogous to the estrus of combustion (though assessed differently than for a hydrocarbon fuel — come across nutrient energy).

Chemical potential energy is a form of potential energy related to the structural organization of atoms or molecules. This arrangement may exist the upshot of chemical bonds. Chemical energy of chemic substances can be transformed to other forms of energy by a chemic reaction. For example, when a fuel is burned, the chemical energy is converted to heat. Green plants transform solar free energy to chemic energy through the process of photosynthesis, and electrical energy can exist converted to chemical energy and vice versa through electrochemical reactions.

The similar term chemical potential is used to indicate the potential of a substance to undergo a change of configuration, be it in the class of a chemical reaction, spatial transport, particle commutation with a reservoir, etc. It is
not
a form of potential energy itself, but is more closely related to free energy. The confusion in terminology arises from the fact that in other areas of physics not dominated by entropy, all potential free energy is available to do useful piece of work and drives the system to spontaneously undergo changes of configuration, and thus at that place is no stardom between “gratuitous” and “not-complimentary” potential energy (hence the one word “potential”). However, in systems of large entropy such equally chemic systems, the total amount of energy present (and conserved according to the get-go police of thermodynamics) of which this chemical potential energy is a office, is separated from the amount of that energy — thermodynamic free energy (from which chemical potential is derived) — which (appears to) drive the organisation forward spontaneously as the global entropy increases (in accord with the
second
law).

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