Question

Which of the following elements has lowest first ionization energy?

Answer 1

The following elements have lowest first ionization energy is Bi

• All the given options of elements belong to the same group 5th  .

• The value of ionization energy (IE) decreases down the group due to the increasing size as the valence electrons are more loosely bound. Thus lowest IE, in this, case is of Bi as it is a bottom-most element.