Boron (5B) naturally occurs as isotopes
B and
B, the latter of which makes up about 80% of natural boron. There are 13 radioisotopes that have been discovered, with mass numbers from 7 to 21, all with short half-lives, the longest being that of
B, with a half-life of only 771.9(9) ms and
B with a half-life of 20.20(2) ms. All other isotopes have half-lives shorter than 17.35 ms. Those isotopes with mass below 10 decay into helium (via short-lived isotopes of beryllium for
B and
B) while those with mass above 11 mostly become carbon.
⭐ Core Definition: Isotopes of boron
HINT:
In this Dossier
Isotopes of boron in the context of Isotopes of carbon
Carbon (6C) has 14 known isotopes, from
C to
C as well as
C, of which only
C and
C are stable. The longest-lived radioisotope is
C, with a half-life of 5700 years. This is also the only carbon radioisotope found in nature, as trace quantities are formed cosmogenically by the reaction
N + n →
C +
H. The most stable artificial radioisotope is
C, which has a half-life of 20.34 min. All other radioisotopes have half-lives under 20 seconds, most less than 200 milliseconds. Lighter isotopes exhibit beta-plus decay into isotopes of boron and heavier ones beta-minus decay into isotopes of nitrogen, though at the limits particle emission occurs as well.