Naturally occurring element X exists in three isotopic

Last updated: 7/27/2022

Naturally occurring element X exists in three isotopic forms: X-28 (27.977 amu, 92.23% abundance), X-29 (28.976 amu, 4.67% abundance), and X-30 (29.974 amu, 3.10% abundance). What is the identity of element X? Al Sr Cu Ni Si