Boron is the 5th element on the periodic table where it is represented by the chemical symbol B. Although compounds containing boron had been known for many centuries, the element wasn’t discovered until 1808 by British chemist Sir Humphry Davy. The metal is never found naturally in its free form on Earth, but is found combined with other elements in certain compounds. All boron found on Earth is comprised of one of two isotopes, but a number of other isotopes have also been identified.
How many isotopes does boron have?
The two naturally occurring stable isotopes of boron are 10B and 11B. About 80.1% of boron found on Earth is 11B and the remaining 19.9% is 10B.
14 unstable (radioactive) isotopes of boron have also been discovered. They all have extremely short half lives with the longest being 8B at just 770 milliseconds followed by 12B at 20.2 milliseconds. All of the remaining unstable isotopes have a half life of less than 17.35 milliseconds. 7B is the most unstable isotope of boron and has the shortest half life at 150 yoctoseconds.
Did you know?
10B is used in nuclear reactors to control nuclear fission and in emergency shutdown systems. Enriched 10B is also used for radiation shielding and in the treatment of some cancers.