Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by form]
6. [materials by chemical form]

Narrower term/s

• strontium isotopes [NP]
• oxygen isotopes [NP]
• nitrogen isotopes [NP]
• lead isotopes [NP]
• radioisotopes
• neodymium isotopes [NP]

Anotations

Scope note:

Forms of a chemical element having the same atomic number but different mass. An isotope is a form of a particular chemical element that shares with other forms the same number of protons in the nucleus, and thus the same atomic number and position in the periodic table, but differs from other forms in the number of neutrons, and therefore the atomic weight.