Isotopes

Definition

Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons. This results in different atomic masses for the isotopes of an element.

5 Must Know Facts For Your Next Test

1. Isotopes of an element share chemical properties but can have different physical properties due to varying masses.
2. Stable isotopes do not decay over time, while radioactive isotopes decay and emit radiation.
3. The presence of isotopes can be detected using mass spectrometry or nuclear magnetic resonance (NMR) spectroscopy.
4. Hydrogen has three common isotopes: protium ($^1H$), deuterium ($^2H$), and tritium ($^3H$).
5. Isotopic notation includes the element symbol, atomic number, and mass number (e.g., $^{14}C$ for carbon-14).

Review Questions

• What distinguishes one isotope from another within the same element?
• How are isotopes used in medical imaging and treatment?
• Explain why isotopes have identical chemical properties but different physical properties.

Related terms

Atomic Number:

The number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.

Mass Number:

The total number of protons and neutrons in an atom's nucleus.

Radioactive Decay:

The process by which an unstable atomic nucleus loses energy by emitting radiation.