A simple ion is formed from a single atom.
ʌ WORD_BOUNDARY s ɪ m p ə l WORD_BOUNDARY aɪ ɑ n WORD_BOUNDARY ɪ z WORD_BOUNDARY f ɔ ɹ m d WORD_BOUNDARY f ɹ ʌ m WORD_BOUNDARY ʌ WORD_BOUNDARY s ɪ ŋ ɡ ə l WORD_BOUNDARY æ t ə m WORD_BOUNDARY