I think the answer is the number of protons.
The compound FeCl3 is made of one atom and three atoms of chlorine
<u><em>explanation</em></u>
- FeCl3 is made up of two elements.
- that is iron with Fe chemical symbol and chlorine with Cl chemical symbol.
- There are 3 atoms of chlorine in FeCl3 because the subscript in front of Cl in FeCl3 is 3.
Answer:
Atoms of the same element, containing the same number of protons, but different numbers of neutrons, are known as isotopes. Isotopes of any given element all contain the same number of protons, so they have the same atomic number
Explanation:
I would say it should be Einstein's famous equation of e=mc^2 which means energy =mass x the speed of light squared. With this equation Einstein showed that energy comes from a mass travelling at the speed of light squared which is a fundamental equation to explain physical phenomena.
