Question

To which of the following elements would it be chemically similar?
(Atomic numbers are given in parentheses.)
N(7) F(9) P(15) Ar(18)

Answer 1

THE ANS IS N AND P BECAUSE THERE VALENCY IS SAME

Answer 2

Nitrogen with atomic number 7 is similar in physical and to some extent chemical properties to Phosphorus with atomic number 15.

If u observe the periodic table keenly, u'll see that these to elements reside in the very same column thus having similar attributes. These two has same valencies i.e same number of electrons in their last orbitals thus similarity comes into the scenario.