Answer:
Explanation:
atomic mass
In 1869, Mendeleev published the first periodic table of the elements. In his periodic table, Mendeleev arranged elements in rows by increasing atomic mass. Within a row, elements with lower atomic masses were on the left. Mendeleev started a new row every time the chemical properties of the elements repeated.
Poop and poopie
Hope this helps!!?!?
Explanation:
a unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.
