A radioactive isotope of hydrogen with a mass approximately three times that of the common protium isotope.
- ‘This particular arrangement of nucleons is unstable and so tritium readily undergoes radioactive decay to yield a helium atom.’
- ‘These products contain tiny glass vials filled with a radioactive gas such as tritium.’
- ‘Although tritium can be a gas, its most common form is in water, because, like non-radioactive hydrogen, radioactive tritium reacts with oxygen to form water.’
- ‘The isotopes tritium and helium - 3 were used to identify and date ground water recharged in the past 50 years.’
- ‘Although many nuclei can be fused, this subject normally refers to fusion of hydrogen isotopes deuterium or tritium to form helium.’
1930s: from modern Latin, from Greek tritos ‘third’.
We take a look at several popular, though confusing, punctuation marks.