Radioactive Decay Flashcards
Name the four types of radiation
Alpha
Beta
Gamma
Neutron
What is an alpha particle?
A helium nucleus
What are the sub-atomic particles in the alpha particle?
Two neutrons + Two protons
What is a beta particle?
A high-speed electron which has been ejected from the nucleus as nuetron turns into a proton
What is Gamma radiation?
A electromagnetic radiation from the nucleus
What is the charge of an alpha particle?
2+
What is the charge of a beta particle?
1-
What is the charge of gamma radiation?
No charge
What does it mean for radiation to be ionising?
When the radiation collides with an atom causing the atom to lose an electron and form an ion
What is the ionising power of alpha particles?
Strongly ionising
What is the ionising power of beta particles?
Quite strongly ionising
What is the ionising power of Gamma radiation?
Weakly ionising
What is the penetrating power of alpha radiation
Weakly penetrating
Is stopped by a single sheet of paper
What is the penetrating power of beta radiation?
Quite penetrating
Is stopped by a few milimetres of aluminium
What is the penetrating power of gamma radiation?
Highly penetrating
Is stopped by several centimetres of lead
What is activity?
The rate at which the source of unstable nuclei decays
What is the unit for activity?
Bq (Becquerels)
What is count-rate?
The number of decays recorded per second by a detector
Why is the count-rate not the same as activity?
The count-rate takes backround radiation into account
What are the sub-atomic particles in neutron radiation
1 neutron, no protons
mass number= 1, atomic number= 0
What is the range in air of alpha particles?
5 cm
What is the range in air of beta particles?
15cm
What is the range in air of gamma radiation?
Several metres
What is the symbol for the alpha particle?
As in what is shown on the periodic table
4He2
What is the symbol for the beta particle?
0e-1
What is the symbol for the neutron particle?
1n0
What happens to the mass number of a particle emiting alpha radiation?
It decreases by 4
What happens to the atomic number of a particle emiting alpha radiation?
It decreases by 2
What happens to the mass number of a particle emiting beta radiation?
It stays the same
What happens to the atomic number of a particle emiting beta radiation?
It increases by 1
What happens to the mass number of a particle emiting gamma radiation?
It stays the same
What happens to the atomic number of a particle emiting alpha radiation?
It stays the same
What happens to the mass number of a particle emiting neutron radiation?
It decreases by one
What happens to the atomic number of a particle emiting neutron radiation?
It stays the same
