Eli5 why is that an atom is 99,6 % empty space ?

Question

Eli5 why is that an atom is 99,6 % empty space ?

In: 332

Answer 1

It’s empty because it’s empty, is the short version. The reason why they can seem so substantial despite being mostly empty is that much of the interaction that atoms have with each other is through the electromagnetic force.

When two objects bump into each other, it’s not the mass of the atoms colliding, it’s the electrons in those atoms repelling each other via their electric fields.