What is the difference in saying "1 mol of nitrogen atoms" and "1 mol of nitrogen molecules"

Explanation:

If we say one mole mole of nitrogen atom it means there is one nitrogen atom present i.e, N. The one mole of nitrogen atom have mass of 14 amu.

If say one mole mole of nitrogen molecule it means  there are two atoms of nitrogen present. N₂

One mole of nitrogen molecule have mass of 28 amu.

Atom:

An atom is the smallest particle of an element, which can take part in a chemical reaction.

The atoms of some elements can not exist independently, while the atoms of some elements can exist independently.

Example:

Helium and Neon atoms are exist as He, Ne while atom of hydrogen, nitrogen etc can not exist as H, N.

Molecule:

A molecule is the smaller particle which can exist independently.

It may be monoatomic , diatomic, triatomic etc.

Foe example,

Hydrogen molecule consist of two atoms H₂

Nitrogen molecule = N₂

It may be combination of atoms of different elements.

HCl, H₂SO₄

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."