15 pts With the exception of one type of hydrogen atom, the atoms of all elements contain protons, neutrons, and electrons. • Identify the subatomic particle that determines the chemical identity of an atom of an element.
• Describe the characteristics of the subatomic particle that determines chemical identity.
• How is the atomic number of an element determined?

um i think it might be a car?

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.