Radioactive Decay Flashcards
What makes an atom’s nucleus stable
If it has a certain amount of neutrons for the amount of protons it has
Name 3 types of radiation
Alpha
Beta
Gamma
What is alpha radiation
When a nucleus has too few neutrons, it emits 2 protons and neutrons called an ‘alpha particle’
What is beta radiation
When a nucleus has too many neutrons, it will change from a neutron to a proton and will emit an electron called a beta particle. This causes the atomic number to increase by one
What is gamma radiation
After emitting a beta or alpha particle, the nucleus will still be too hot, and will cool down by emitting an electromagnetic wave, which is called a gamma ray. This causes no change to the atomic or mass number
State the penetration power of the 3 types of radiation
Alpha - Skin/Paper
Beta - 3MM Aluminium/Foil
Gamma - Lead/Concrete
What is half-life
Half-life is the time it takes for half of the unstable nuclei in a sample to decay or for the activity of the sample to halve or for the count rate to halve.
What is count rate
Count-rate is the number of decays recorded each second by a detector
What is an example of a detector
Geiger-Muller Tube
How do alpha particles effect an atomic number
It changes the mass number by -4 and the atomic number by -2
How do beta particles effect an atomic number
It changes the atomic number by +1
How do gamma particles effect an atomic number
It has no effect
