+ If the cost of electricity required
to deposit lg of Aluminum
is #4.00, how
much would it
Cost to deposit 24g of Copper
[AL=24 Ca=64]

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.