What are the important uses of alpha beta and gamma radiation a brief description?

Answer 1

USES OF ALPHA,BETA,GAMMA,POSITRON DECAY

Alpha Decay e.g. the nuclear equation

• A helium nucleus, the alpha particle, of 2 protons and 2 neutrons is emitted at high speed/kinetic energy from the nucleus.

• The residual atom (sometimes referred to as the politically incorrect 'daughter nuclide'!*) has a mass number of 4 less, and an atomic number of 2 less, than the 'parent' or original atom.

• Most atoms with an atomic number of over 82 (Pb) usually undergo alpha decay.

• * Sadly, apart from Marie Curie and her daughter, in the late 19thC/early 20thC, nuclear physics was dominated by male scientists!

Beta- Decay e.g. the nuclear equation

• A neutron in the nucleus changes spontaneously into a proton and a high kinetic energy electron forms the emitted beta particle.

• Since the proton and neutron have a mass of 1 and the electrons mass is negligible, the mass number stays the same but the atomic (proton) number rises by 1.

• This tends to happen with isotopes with too many neutrons to be stable (too high an n/p ratio) and lies above the stability curve shown above.

• By changing a neutron to a proton the n/p ratio is reduced to the nucleus of an isotope lying in the stability band.

• Balancing: The changes can be represented as nuclear equations and they must balance in mass number and nuclear or emitted particle charge (protons in alpha decay, protons and electrons in beta decay).

• In (1) mass = 235 = 231 + 4 and protons = 92 = 90 + 2.

• For (2) mass = 14 = 14 + 0 and for protons/beta charge = 6 = 7 + (-1). In either case a new element is formed i.e. the 'transmutation' of one element to another has happened. It also means that there can never be a 'pure' Radioisotope.

Positron emission is required by some syllabuses

• + Positron emission (beta+ decay)

• e.g.

• A proton changes to neutron and a 'positive electron' called a positron is expelled with very high kinetic energy. A positron has the same mass as an electron but carries a positive charge (it is the 'anti-matter' particle of the electron!).

• Since the proton and neutron have a mass of 1 and the electrons mass is negligible, the mass number stays the same but the atomic (proton) number falls by 1.

• This tends to happen with isotopes with too few neutrons to be stable (too low an n/p ratio) and lies below the stability curve shown in a previous graph. By changing a proton to a neutron the n/p ratio is increased to an isotope lying in the stability band.

Gamma emission: The emission of gamma radiationfrom a nucleus does not involve any change in the atomic (proton) number or mass number.

• When a 'new' nucleus is formed it tends to have excess energy making it potentially unstable.

• To become more 'nuclear stable' the nucleus loses some energy as a burst of gamma radiation but the proton and neutron numbers do not change.

Answer 2

Alpha radiation particles are big, heavy, slow and weak. Because they are so big, they bash into atoms and knock electrons off - this creates ions. They are too weak to penetrate, but once breathed in, it causes damage internally. ALPHA particles are POSITIVELY CHARGED.

Beta radiation particles are small, medium-weight, and fast. For every Beta-particle emmited, the number of protons increased by one. BETA particles are NEGATIVELY CHARGED.

Gamma radiation particles are tiny, have no weight and are really fast. Gamma particles don't really hit or collide with anything, they usually pass through although it does damage. They enter the body via penetration and causes damage before leaving the body. GAMMA particles have NO CHARGE.