From The Student Room

TSR Wiki > Study Help > Subjects and Revision > Revision Notes > Chemistry > Definitions of Relative Atomic Mass, Isotope, Atomic No.

---

Contents 1 Atomic Number / Proton Number 2 Mass Number / Nucleon Number 3 Isotope 4 Nuclides 5 Comments

Atomic Number / Proton Number

Number of protons in the nucleus

Mass Number / Nucleon Number

Total number of protons and neutrons in the nucleus

Isotope

Atoms with the same atomic number but different number of neutrons therefore a different atomic mass.

Nuclides

A specific nucleus eg Cl - 35 and Cl - 37 Relative atomic mass: The mass of an atom to 1/12 of the mass of a carbon-12 atom.

Comments