I think it's 2 I tried looking it up because I was not sure.
Heating up, mostly. Solid can be heated to liquid, then to gas, then eventually to plasma.
In a Lewis structure, formal charges can be assigned to each atom by treating each bond as if one-half of the electrons are assigned to each atom. ... Resonance occurs in cases where two or more Lewis structures with identical arrangements of atoms but different distributions of electrons can be written.
Answer: protons and electrons
Explanation: In a neutral atom there are always equal numbers of protons and electrons.