Question
The electronic states $$X$$ and $$Y$$ of an atom are depicted below :
$$\eqalign{
& X:1{s^2}2{s^2}2{p^6}3{s^1} \cr
& Y:1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}4{s^1} \cr} $$
Which of the following statements is not correct?
A.
$$X$$ represents an alkali metal.
B.
More energy is required to remove an electron from $$X$$ than from $$Y.$$
C.
$$Y$$ represents ground state of the element.
D.
Less energy is required to remove an electron from $$X$$ than from $$Y.$$
Answer :
Less energy is required to remove an electron from $$X$$ than from $$Y.$$
Solution :
Due to small size of atom $$X\left( {n = 3} \right)$$ than $$Y\left( {n = 4} \right),$$ the electron present in $$3{s^1}$$ orbital is more attracted towards the nucleus. Hence, greater amount of energy is required for the removal of this valence electron from $$X$$ as compared to $$Y.$$