Radioactivity Flashcards
What is an ion?
An ion is a charged atom. They occur when an atom loses or gains electrons.
What is a isotope?
An isotope is an element with the same number of protons but different number of neutrons. Most isotopes are unstable this means they emit radiation form the nucleus in an attempt to stabilise.
What are the different types of radiation?
Alpha, Beta and Gamma
How do you show an alpha particle?
4 a or 4 He
2 2
How do you show a beta particle?
Beta articles are fast moving electrons.
0 B or 0 e
-1 -1
How do you show a gamma particle?
0 y
0
Describe structure of alpha particles
2 protons
2 neutrons
+2 charge
Describe the structure of beta particles
0 protons
0 neutrons
-1 charge
Describe the structure of gamma particles
0 protons
0 neutrons
no electrical charge
What happens when a nucleus emits an alpha particle?
If a nucleus emits an alpha article:
mass no. decreases by 4
atomic no. decreases by 2
When an alpha article is emitted both mass number and charge change.
What happens when a nucleus emits a beta particle?
If a nucleus emits a beta particle:
loss of neutron (as it changes into a proton)
mass no. stays the same
atomic no. increases by 1
In beta radiation mass of nucleus stays them same however charge changes.
What happens when a nucleus emits a gamma particle?
Gamma radiation is emitted after either alpha or beta radiation had occurred. The nucleus structure does not change, as it is only energy that is removed.
Some unstable nuclei may give out a neutron this occurs mass no. decreases by 1.
What are the properties of an alpha particle?
strong ionising power
weak penetration power
travel 3-5 cm in air
stopped by a sheet of paper.
What are the properties of a beta particle?
moderate ionising power
moderate penetration power
travel up to 1 metre in air
stopped by a sheet of aluminium
What are the properties of a gamma particle?
weak ionising power
high penetration power
travel over 21 km in air
stopped by 5-10 cm of lead or 5-10 metres of concrete
Define contamination
Radioactive contamination is the unwanted presence of a reactive isotope on other materials.
being irradiated by the source
What is the hazard from contamination?
the hazard of contamination relies on the decay of the contaminating atoms releasing alpha, beta or gamma radiation.The type of radiation affects the level of hazard.
Define irradiation
Irradiation take place if an object is exposed to a source which is emitting radiation.
What is the hazard from irradiation?
Irradiation can ionise the atoms in your cells
radiation ionising your cells. Ionisation can lead to cell mutation.
Safety precautions to avoid contamination
protective clothing (goggles,gloves and suits)
rapid response team
isolate the source
remove the substance
