Radiochemistry

Radiochemistry deals with the use of radioactivity to study ordinary chemical reactions. All radioisotopes—unstable isotopes of elements—undergo nuclear decay and emit some form of radiation. The radiation emitted can be one of three types, called alpha, beta, or gamma radiation.

1. α (alpha) radiation - the emission of an alpha particle (which contains 2 protons and 2 neutrons) from an atomic nucleus. When this occurs, the atom’s atomic mass will decrease by 4 units and atomic number will decrease by 2.

2. β (beta) radiation - the transmutation of a neutron into an electron and a proton. After this happens, the electron is emitted from the nucleus into the electron cloud.

3. gamma radiation - the emission of electromagnetic energy (such as X-rays) from the nucleus of an atom. This usually occurs during alpha or beta radioactive decay.

These three types of radiation can distinguished by their difference in penetrating power.

Alpha can be stopped quite easily by a few centimetres in air or a piece of paper and is equivalent to a helium nucleus. Beta can be cut off by an aluminium sheet just a few millimetres thick and are electrons. Gamma is the most penetrating of the three and is a massless chargeless high energy photon. Gamma radiation requires an appreciable amount of heavy metal radiation shielding (usually lead or barium-based) to reduce its intensity.

Radiochemistry is the field of science that analyses those reactions based on radioactive emanations. Radiochemistry also includes the production of radionuclides and their compounds by processing irradiated or naturally occurring materials that have ostensible radioactive attributes.

Radiochemistry is more closely linked to nuclear chemistry, with the application of chemical techniques to nuclear studies and the application of radioactivity to the investigation of chemical and biochemical problems being a theatre of research paramount to it.

There are many natural occurring substances that contain radioactive elements in sufficient quantity, well known examples of these elements are uranium (U), radium (Ra) and thorium (Th).