Polyatomic number are ions made up of more than one atomic element
polyatomic ions are those ions which carry more than one atom,we can say that a group of atoms having single charge( which may be positive or negative) are polyatomic ions.
No, Methane (CH4) is not a polyatomic ion. It doesn't have a charge, therefore it can't be an ion. It's considered a hydrocarbon.
A polyatomic Radical is a atom that differs from other because it has come into contact with a massive energy force and fused it into a different form
Oxygen
Solid sodium is a metal, there is a lattice of sodium atoms with a "cloud" or sea of electrons delocalised across it.#