Atomic Structure-atoms and nuclear radiation Flashcards
Why do unstable nuclei give out radiation?
Unstable radiation undergo decay to become more stable
As they release radiation their stability increases
What is the name of the process in which an unstable nucleus gives out radiation to become more stable?
Radioactive decay
Define the activity of an unstable nucleus?
Activity is the rate of decay of a source of unstable nuclei
What is the unit of radioactive activity?
Becquerel(Bq)
What is count-rate?
The number of radioactive decays per second for a radioactive source
Give an example of a detector that may be used to measure count rate?
Geiger-Muller tube
State four types of nuclear radiation?
Alpha particles
Beta particles
Gamma particles
Neutrons
What are the constituents of an alpha particle?
Two protons and two neutrons
It is the same as a helium nucleus
What is the range of an alpha particle through air?
A few centimetres
What will stop beta radiation from passing through a point?
A thin sheet of aluminium
Several meters of air
What will stop gamma radiation from passing through a point?
Several centimetres of lead
Few meters of concrete
What type of radiation is most ionising
Alpha radiation
Which type of radiation is least ionising?
Gamma radiation
State any changes to mass or change that occur due to the emission of a gamma ray?
Both mass and charge remain unchanged
Describe the nature of radioactive decay?
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