Isotopes
Learn about isotopes, mass number, and atomic mass. Understand how isotopes are named. Calculate the atomic mass of an element using a sample of its isotopes.
▶ Isotopes
Isotopes are atoms of the same element with different numbers of neutrons. Since isotopes of an element have different numbers of neutrons, they also have different masses. The sum of the number of neutrons and protons in an atom is called its mass number. Isotopes can be represented in writing using isotope notation.
▶ Worked example: using the mass number equation
The sum of the number of neutrons and protons in an atom is called its mass number. If we know the mass number of an atom, we can determine the number of neutrons in its nucleus.
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