Solid aluminum reacts with oxygen gas to form solid aluminum oxide. If 6.1 moles of aluminum reacts with excess oxgyen gas, how many moles of aluminum oxide can be formed

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.

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.