Question
Chemistry Question on Classification of elements & periodicity in properties
The spectrum of helium is expected to be similar to that of
A
H
B
Na
C
Li+
D
He+
Answer
Li+
Explanation
Solution
The spectrum of an atom depends on the number of electrons present in it. Here, helium has two electrons, so the spectrum of Li+ (Z = 3) is similar to that of helium because both He and Li+ have two electrons.