Question

Which ion has the same electron configuration as an atom of He?

Answer 1

It's H- since He has only 2 electron and so does H-

Answer 2

Answer;

H- (negatively charged hydrogen ion)

Explanation;

The hydrogen ion has the same electron configuration as an atom of Helium. -Hydrogen ion is formed when a hydrogen atom loses or gains an electron. A positively charged ion is formed when hydrogen atom loses an electron (remaining with zero electrons) while a negatively charged ion (H-) is formed when a hydrogen atom gains an electron thus having 2 electrons.

-Helium atom has two electrons, therefore, it is similar with an negatively charged hydrogen.