Alpha, Beta and Gamma Radiation Flashcards
What are Alpha particles
Helium Nuclei
What are Beta particles
Electrons
What are gamma rays?
Very short wavelength EM Waves
What are alpha particles made up of?
2 protons and 2 neutrons.
What are alpha particles?
They are helium nuclei. They’re heavy and slow-moving. They are made up of 2 protons and 2 neutrons. They therefore don’t penetrate far into materials but are stopped quickly
Alpha particles are “strongly ionising”. What does this mean? (ionising power)
They bash into a lot of atoms and knock electrons off them before they slow down and create lots of ions.
How well do alpha particles penetrate materials?
They are heavy and slow moving. They therefore don’t penetrate far into materials but are stopped quickly
Which is the most ionising? Alpha particles, beta particles or gamma rays.
Alpha particles.
Which is the least ionising? Alpha particles, beta particles or gamma rays.
Gamma rays
Because alpha particles are electrically charged (with a positive charge)……
….alpha particles are deflected (their direction changes) by electric and magnetic fields.
What happens to the atomic number and mass number when an alpha particle is emitted?
The atomic number of the nucleus decreases by 2 and the mass number decreases by 4.
What is the helium nuclei?
Alpha particles.
He, Mass number 4 and Atomic number 2
What is a beta particle?
A beta particle is an electron which has been emitted from the nucleus of an atom when a neutron turns into a proton and an electron.
What happens when a beta particle is emitted?
The number of protons in the nucleus is increased by 1. So the atomic number is increased by 1 but the mass number remains the same.
How well do beta particles penetrate materials?
They move quite fast and are quite small. Therefore they penetrate moderately before colliding.
What is the ionising power of beta particles?
They are moderately ionising. Because they are charged (negatively), beta particles are deflected by electric and magnetic fields.
Why are gamma rays the opposite to alpha particles?
They have no mass. They are just energy in the form of an EM wave.
How well do gamma rays penetrate materials?
They can penetrate a long way into materials without being stopped.
What is the ioning power of gamma rays?
Because they can penetrate a long way into materials, they are weakly ionising as they tend to pass through rather than collide with atoms. But eventually they hit something and do damage.
What is the charge of a gamma ray?
They have no charge so they are not deflected by electric or magnetic fields.
Gamma rays are not deflected by electric or magnetic fields because…..
….. they have no charge.
When does gamma emission occur?
After alpha or beta decay
What happens to the atomic number and the mass number after gamma emission?
There is no effect on the atomic or mass numbers of the isotope
What happens if a nucleus has excess energy?
it loses this energy by emitting a gamma ray
What is the maximum range of a beta particle in air.
50 cm
