There are so many examples of exothermic reactions that is the reactions in whoch energy is released. All the oxidation reactions are exothermic reactions . similarly hydrogenation of alkenes like...
Only a chemical reaction or physical process can be exothermic, not an element.
Any chemical reaction that releases energy. such as burning gasoline, living
A siren, a spaghetti dinner, a black cat. Better questions usually get better answers.