alleryStart learning →What decides which element an atom belongs to?
AIts number of neutrons
BIts number of protons
CIts number of isotopes
DIts number of orbits
Answer & Solution
Correct answer: B. Its number of protons
1. An atom's nucleus holds protons and, in most cases, neutrons as well.
2. The count of protons fixes the identity of the element.
3. Six protons make carbon, eight make oxygen and twenty six make iron.
4. Changing the neutron count only gives a different isotope of the same element.
_Source: OpenStax Astronomy (CC BY 4.0), Ch 4 "Earth, Moon, and Sky" and Ch 5 "Radiation and Spectra", section 5.4 The Structure of the Atom_
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