Question

the mono univalent cation whose spectrum is similar of He is​

Answer 1

The mono univalent cation whose spectrum is similar to He is​ H.

Explanation:

• Helium is a mono univalent cation when one electron is removed and it has only one electron in its outermost shell.
• The mono univalent cation is He+.
• This mono univalent cation si similar to hydrogen atoms as both have only one electron in their outermost shells.
• Therefore, their spectrum is also the same and they both show similar spectral and transition lines.

Answer 2

$\huge \tt Hydrogen \: \: (H)$