Explanation: The atoms of each element differ from those of all other elements in the number of protons. If Ryan found out how many protons the element had, he would be able to identify the element.
An atomic mass unit (symbolized AMU or amu) is defined as precisely 1/12 the mass of an atom of carbon-12. The carbon-12 (C-12) atom has six protons and six neutrons in its nucleus.
