Capracus
27th October 2011 - 09:41 AM
Energy is an attribute of a substance as a consequence of its atomic, molecular or aggregate structure.
Capracus
28th October 2011 - 04:36 AM
Since a chemical transformation is accompanied by a change in one or more of these kinds of structure, it is invariably accompanied by an increase or decrease of energy of the substances involved.
Capracus
29th October 2011 - 06:06 AM
Some energy is transferred between the surroundings and the reactants of the reaction in the form of heat or light; thus the products of a reaction may have more or less energy than the reactants.
Capracus
31st October 2011 - 03:11 AM
A reaction is said to be exergonic if the final state is lower on the energy scale than the initial state; in the case of endergonic reactions the situation is the reverse.
Capracus
31st October 2011 - 12:52 PM
A reaction is said to be exothermic if the reaction releases heat to the surroundings; in the case of endothermic reactions, the reaction absorbs heat from the surroundings.
Capracus
1st November 2011 - 03:03 AM
Chemical reactions are invariably not possible unless the reactants surmount an energy barrier known as the activation energy.
Capracus
2nd November 2011 - 03:11 AM
The speed of a chemical reaction (at given temperature T) is related to the activation energy E, by the Boltzmann's population factor e − E / kT - that is the probability of molecule to have energy greater than or equal to E at the given temperature T.
Capracus
3rd November 2011 - 06:52 AM
This exponential dependence of a reaction rate on temperature is known as the Arrhenius equation.