1. in the chemical equation above, name the reactant(s)
and product(s).

There ain't enough info in the question to answer but, I can say that reactants were there before the reaction, but products were produced by the reaction.

Explanation:

I don't really know how to answer this.

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.