Hi! I have understood how elements such as Be and Ca, with fully filled 2s orbitals, are not to be considered "noble" because they still have unfilled p orbitals. But I'm having trouble understanding how these elements participate in chemical reactions without having any unpaired electrons. My understanding is that for an atom to bond (ionically or covalently) it has to have an unpaired electron. Is that incorrect? If yes, can you please explain how? Thanks so much!