# What is difference between valence electron and free electron?

If you look at the energy perspective, understanding valence electrons or free electrons is simple. Every particle in the universe has some potential to influence other particles. Potential is in a sense the desire of a particle to be near another.

The positively charged nucleus of an atom provides electrons with a potential well. This well is infinitely deep, and gets deeper as the electron moves closer to the nucleus. It can be described as: A girl (electron), is attracted to a man (nucleus). He is very social and she has a lot of interaction with him. The deeper her attraction, the greater. This interaction level is similar to the depth of the potent well, so more interaction equals deeper well.

Because electrons orbit around the nucleus, they are attracted to it (hence why electrons prefer to be near the nucleus). Imagine that you are really mean and want to break the attraction between the electrons and the nucleus. The electrons want to be near the nucleus so you need to give them an even greater incentive. It’s as if you were attracted to a girl (electron), but you are determined to get the girl for yourself. You must convince her that you are the best choice for her and not the guy to make her your girlfriend. This impetus/reason is technically energy. You must give/put energy into the nucleus electron system so that the electron has enough energy to escape the nucleus. Remember that the electron is attracted to the nucleus and won’t leave the nucleus by itself.

A valence electron, then, is an electron which is located in the vicinity the nucleus’ potential well, but not very far inside the well. I.e. This electron is not attracted to the nucleus so it doesn’t take as much energy to get it to leave. It would be similar to a girl with a passing interest in a man and who would rather date him, but doesn’t know much about him and is open to other men if the opportunity presents itself.

A free electron is one that isn’t under the influence from the potential well. You have broken the attraction between an electron and the nucleus and it now wanders the universe looking for another nucleus. This is a great analogy for romance! :'(

We hope this helps! 🙂