Question: When you add two elements together why is it that they become a compound (two atoms joined together) rather than the two atoms become a new 1 atom. I get that you can't create a new element but why is it that a compound is atoms joint together and not a new atom like when you mix flour and milk it isn't flour wrapped round milk or milk wrapped round flour they mix so that you can't separate them (like a compound) but they become batter. Why?

Peter Boorman answered on 17 Nov 2016:

Hi 15madthr,

This is maybe one of my favourite questions I’ve had in the competition so far. I also really liked your analogy of milk and flour – well explained!

The reason that two atoms don’t mix to become a new atom, is just because of the amounts of energy you need to do it. It turns out that you need a lot less energy for two atoms too combine to form a molecule, because the forces involved are weaker than those involved with binding the individual sub-atomic particles responsible for creating new atoms. If you had enough energy, (for example these energies are achievable at the Large Hadron Collider experiment in Switzerland), you can ‘probe’ the smallest regions of atoms, and potentially combine atoms into a new atom.

Peter