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ISOTOPES

After reading this section you will be able to do the following:

  • Define an isotope and explain how it is different than an element.

The other particle in the nucleus of an atom is the neutron. The neutron has no electrical charge and is said to be neutral. Like protons, all neutrons are identical.

Do all atoms of an element have the same number of neutrons?

The answer to this question is no. The number of protons in the nucleus of every atom of an element is always the same, but this is not the case with the number of neutrons. Atoms of the same element can have a different number of neutrons. Atoms want to have the same number of neutrons and protons but the number of neutrons can change.

Notice that the three hydrogen atoms have the same number of protons, but a different number of neutrons. These atoms are called isotopes, which are atoms of the same element that have a different number of neutrons.

Review:

  1. Neutrons are all identical to each other, just as protons are.
  2. Atoms of a particular element must have the same number of protons but can have different numbers of neutrons.
  3. When an element has different variants that, while all having the same number of protons, have differing numbers of neutrons, these variants are called isotopes.