A student makes an aqueous solution of sodium hydroxide. Which statement correctly identifies the two ions present in the solute of this mixture? A. The sodium ion is positive, and the hydroxide ion is negative.
B. The sodium ion is neutral, and the hydroxide ion is neutral
C. The sodium ion is positive, and the hydroxide ion is positive.
D. The sodium ion is negative, and the hydroxide ion is positive.

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.