What is hydroxide ion concentration in an aqueous solution with a hydrogen ion concentration of 2.70 x 10^-2 M?

i'm pretty sure it is letter c.) car

12 is it do you think so

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.