The percent by mass of sodium chloride in a solution of 14.0 g of sodium chloride in enough water to make 91.0 g of solution is:

i had this on my unit activity, i can you if you are a plato student. are you a plato student?

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.  

yes the answer is total mass in unchanged   : )