What does the atomic number mean or represent? also how do i make someone brainliest

The atomic number refers to the number of protons in the nucleus of an atom. The identity of an element is determined by its number of protons. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus.

And if you want to mark someone's answer as brainliest first you have to get more than 1 answer to your question and then there will be a message above that says “Mark as brainiest”

the answer is true.

"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."