How does alpha particles work

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Radiation is energy. It can come from unstable atoms that undergo radioactive decay , or it can be produced by machines. Radiation travels from its source in the form of energy waves or energized particles. There are different forms of radiation and they have different properties and effects. Non-ionizing radiation has enough energy to move atoms in a molecule around or cause them to vibrate, but not enough to remove electrons from atoms.

Examples of this kind of radiation are radio waves, visible light and microwaves. Ionizing radiation has so much energy it can knock electrons out of atoms, a process known as ionization. Ionizing radiation can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes. Ionizing radiation comes from x-ray machines, cosmic particles from outer space and radioactive elements.

Radioactive elements emit ionizing radiation as their atoms undergo radioactive decay. Radioactive decay is the emission of energy in the form of ionizing radiation ionizing radiation Radiation with so much energy it can knock electrons out of atoms.

The ionizing radiation that is emitted can include alpha particles alpha particles A form of particulate ionizing radiation made up of two neutrons and two protons.

A further example of neutron emission is in nuclear fission reactions , where neutrons are released from the parent nucleus as it splits. Neutron emission causes the mass number of the nucleus to decrease by one and the atomic number remains the same. The different types of radiation are often compared in terms of their penetrating power , their ionising power and how far they can travel in the air. All types of radioactive decay can be detected by a Geiger-Muller tube, or G-M tube.

The radiations ionise the gas inside and the resulting charged particles move across the chamber and get counted as charges rather like an ammeter.

Because the nucleus is unstable a piece of it is ejected, allowing the nucleus to reach a more stable state. The piece that is ejected is the alpha particle , which is made up of two protons and two neutrons: this is the nucleus of the helium atom.

Helium is an inert and harmless gas, so the particles are not dangerous in themselves, it is only because of the high speeds at which they are ejected from the nuclei that they become dangerous. At these high speeds they have enough energy to break bonds in matter or ionise atoms knock electrons off , which is especially deleterious for living cells. There are three main types of ionising radiation emitted from the unstable nuclei of radioactive atoms - these are alpha, beta and gamma radiation.

Alpha radiation consists of alpha particles. An alpha particle is identical to the nucleus of a helium atom, which comprises two protons and two neutrons.