[alawsareps]

What I know is... Stable means atom with no charge (positive or negative)


https://www.youtube.com/watch?v=Bjf9gMDP47s at 01:55.

Aluminum has 13 protons and electrons, just balance, that means it is stable...

In Metallic Bonding, why would it need to detach those 3 valence electrons?

[Borek]

That's a lousy definition of what "stable" is.

If an atom has identical number of electrons and protons it is neutral, but it can be still highly reactive and willing to either easily give away or take in an electron (or a few). Yes, a separated (as in cold vacuum), neutral atom is stable, but we rarely deal with separated, single atoms, typically we work with samples that contain huge number of interacting atoms.

[alawsareps]

nevermind got the answer

[Vidya]

https://www.youtube.com/watch?v=bVpK98ax6Ag
Please check this video to understand why ions are formed .I am sure you will get your answer.

[Enthalpy]

In a metal, the electrons aren't away from the nucleus. They're only shared among many nuclei. The essential energetic benefit is that the metallic electrons have a huge room to delocalize in, which implies (for many of them) that their kinetic energy is smaller.