Question

How can He2+ exist without existence of he2 as He2+ must be made from He2 itself. ​

Answer 1

Answer:

The molecular orbital configuration is based on the number of electrons. The number of electrons in is 4. When bond order is 0, such a molecule does not exist. The bond order is not equal to 0, hence this molecule exists.

Answer 2

$\huge \underline \bold \color{coral} \mathcal{HEYA }$

Helium has 1s2 electronic configuration and is a stable element with bond order zero. Hence, it can't accept or donate electrons to any element to make a compound. That is why He2 compound doesn't exist.

While in the second case, there is positive charge on one helium atom which means it has 1s1 electronic configuration and needs one more electron to become stable. This is the reason why He2+ compound can exist.

Hope it helps ✌️ ✌️