What is exothermic and endothermic reaction ?​

Exothermic reaction is a reaction that involves the release of heat, while a endothermic reaction is a reaction that involves the absorption of heat

Explanation:

A example of a exothermic reaction would be the process a liquid goes through when put in cold temperatures which causes the liquid to change it's state into a solid. A example of a endothermic reaction would be melting that solid changing it's state back into it's original state a liquid.

Hope this helps.

exothermic reaction

Se denomina reacción exotérmica a cualquier reacción química que desprenda energía, ya sea como luz o calor

endothermic reaction

Un proceso endotérmico es cualquier proceso con un aumento en la entalpía H (o energía interna U) del sistema

If you translate it, you will find the answer

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge