Which one of the following represents an acceptable set of quantum numbers for an electron in an atom? (arranged as n, l, ml, and ms) 2, 2, -1, -1/2

3, 3, 3, 1/2

3, 3, 3, -1/2

5, 4,- 5, 1/2

2, 1, 0, 1/2

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.