Question

How would you react to this statement?
Electronegativity of nitrogen (N) on Pauling scale is 3.0 in all the nitrogen compounds.

Answer 1

This case is not possible because the electronegativity of nitrogen will change or depends on the atoms that are attached to it. Electronegativity of nitrogen gets affected by its hybridization and the oxidation state. For different compounds electronegativity will be different.

Complete answer:
According to Linus Pauling electronegativity is the power of an atom to attract electrons towards itself in a molecule. When an atom is bounded with other atoms in a compound the electronegative of an atom can be checked through its ability to attract the electron density towards itself. Atoms with higher electronegativity will attempt more to pull an electron from the atom that is bonded with it and attract the electron toward itself.
Electronegativity of an element will be variable in different cases, it depends on the other atoms that are bonded with them in a compound.
So, the electronegativity of nitrogen in all the nitrogen compounds on Pauling scale cannot be 3.0 always. For example in $N{{O}_{2}}$ and $N{{H}_{3}}$ the electronegativity value of nitrogen will be different because they are attached with different atoms.
Electronegativity also depends upon the state of hybridization and oxidation state of elements.
Electronegativity will increase if the oxidation state will increase it will not remain the same. For example the oxidation state of nitrogen in $N{{O}_{2}},NO$ and ${{N}_{2}}O$ is different.
The oxidation state of N in $N{{O}_{2}}$ is +4, Oxidation state of nitrogen in $NO$ is +2 and the oxidation state of nitrogen in ${{N}_{2}}O$ is +1.
Therefore the electronegativity of nitrogen will be more in the following order $N{{O}_{2}} > NO > {{N}_{2}}O$
Thus the statement that electronegativity of nitrogen (N) on Pauling scale is 3.0 in all the nitrogen compounds is incorrect.

Note:
Electronegativity depends on the percentage s character of the elements, more the % s character more will be the electronegativity. Hence the electronegativity of nitrogen will increase from $s{{p}^{3}}$ to $sp$,therefore the electronegativity trend will be $s{{p}^{3}} < s{{p}^{2}} < sp$. Electronegativity depends upon the atomic radius and the atomic number.