Hydrogen is the first element in the periodic table. It has the simplest electronic configuration 1s1. It contains one proton in the nucleus and one electron.
Isotopes:- Atoms of the same element having same atomic number but different mass number are called isotopes.
There are three isotopes for hydrogen with mass numbers 1, 2 and 3, each possessing an atomic number of one.
Tritium, 1H3 or 1T3: It occurs in the upper atmosphere only where it is continuously formed by nuclear reactions induced by cosmic rays. Unlike deuterium, it is radioactive, with a half-life of ~ 12.3 years. It's nucleus consists of one proton and two neutrons.
Tritium 1H3: It is a rare isotope of hydrogen. Its traces are found in nature due to nuclear reactions induced by cosmic rays.
Tritium is prepared by
i) By bombarding lithium with slow neutrons
3Li6 + on1 -- > 1T3 + 2He4
ii) By bombarding beryllium with deuterons
4Be9 + 1D2 -- > 1T3 + 4Be8
4Be9 + 1D2 -- > 1T3 + 2 2He4
Properties : It is radioactive with a half-life of 12.4 years. It decays into helium -3 with the emission of beta radiation.
1T3 -à ß- 2He3 + -1eo
It is used as a radioactive tracer in chemical research.
It is used in nuclear fusion reactions.