Which from following is NOT hydrogen like species?

Step-by-step solution

A hydrogen-like species is defined as having only one electron. Li +2 : Lithium has atomic number 3, so Li +2 has 3 - 2 = 1 electron, making it hydrogen-like. Be +3 : Beryllium has atomic number 4, so Be +3 has 4 - 3 = 1 electron, making it hydrogen-like. Li + : Lithium has atomic number 3, so Li + has 3 - 1 = 2 electrons, which is not hydrogen-like. He + : Helium has atomic number 2, so He + has 2 - 1 = 1 electron, making it hydrogen-like. Thus, the species that is not hydrogen-like is Li ⁺ , corresponding to opti