What is the oxidation number of Na in Na(s) in 2 Na(s) + 2 HCl(aq) → 2 NaCl(aq) + H2(g)

b is the correct

the answer would be b i believe

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.