An atom

Select $2$ correct answer$($s$)$

may possess a maximum of eight electrons in the inmost orbital

has a mass number that depends partially on the number of neutrons that it contains

of oxygen is stabler than an atom of sodium or chlorine

possesses orbitals external to the inmost one, which accommodate a maximum of six electrons

known as carbon has an atomic mass of ~~$6$

may lose or gain an electron, after which it remains a nonionic atom