If by energy you mean heat energy exothermic reactions.
All reactions gives out energy
Exothermic reaction gives free heat (energy).
Exothermic reaction gives free heat (energy).
Exotherm is a reaction that gives out energy . Exergy is the proper name for giving out energy ala exercise and exert, the key syllable is 'ex' for 'out'.
A reaction that gives off energy
... is an exothermic reaction (opposite of 'endothermic')
A chemical reaction that produces energy is said to be exothermic. In comparison, if it consumes energy it is endothermic.
Endothermic
Yes. Such a reaction is called an endothermicreaction.
The scientific name for the reaction that gives out energy is exothermic
alternative energy
An Endothermic reaction. If you touch the reaction vessel it will feel cool/cold, as it is taking in heat energy. By contract an Exothermic reaction is one that gives out heat. If you touch the reaction vessel it will feel warm/hot as it is liberating heat energy.
Activation energy is needed to start a chemical reaction. This energy is used to join the reactants together or break them apart. If a reaction is exothermic then it gives energy out. If it is endo thermic then the reaction takes energy in.