Isotopes, Nuclear Stability, and Atomic Mass Calculations

Vocabulary flashcards covering the core characteristics, notation, hydrogen configurations, stability classifications, and atomic mass calculations of isotopes.

Isotopes

Different versions of an atom of the same element that contain the same number of protons but a different number of neutrons.

Protium ($^{1}\text{H}$)

The hydrogen isotope configuration containing $1$ proton and $0$ neutrons.

Deuterium ($^{2}\text{H}$)

The hydrogen isotope configuration containing $1$ proton and $1$ neutron.

Tritium ($^{3}\text{H}$)

The hydrogen isotope configuration containing $1$ proton and $2$ neutrons.

Chemical Behavior of Isotopes

The principle that isotopes of the same element react almost identically in chemical processes because chemical reactions are driven by electron configurations.

Isotope Effect

Minor variations in physical properties—such as density, melting point, and boiling point—exhibited by isotopes due to differences in their mass.

Mass Number ($A$)

The total number of protons plus neutrons ($A = \text{protons} + \text{neutrons}$) used to designate specific isotopes (e.g., carbon-12 has $6$ neutrons, while carbon-14 has $8$ neutrons).

Stable Isotopes

Isotopes that maintain a permanent, non-decaying nuclear configuration over time, such as carbon-12.

Radioisotopes

Radioactive isotopes that possess an unstable ratio of protons to neutrons, causing them to spontaneously emit radiation (alpha particles, beta particles, gamma rays) to reach stability.

Half-Life

The fixed rate of decay representing the time required for half of the radioactive atoms in a sample to decay, ranging from fractions of a second (e.g., Lithium-8) to billions of years (e.g., Uranium-238).

Atomic Mass Unit (amu)

The standard unit of mass used to quantify the mass of individual atoms and isotopes.

Average Atomic Mass

The weighted average of the masses of an element's naturally occurring isotopes, calculated as $\sum (\text{isotope mass} \times \text{fractional abundance})$.