4: Atomic Structure Flashcards
What’s an ion?
An ion is formed when an atom loses or gains electrons, giving it a net charge
What’s the radius of an atom?
10^-10 m
What’s the relative mass of an electron?
1/1800
What did Bohr do?
Suggested electrons orbited at different energy levels
What did Chadwick do?
PROVED the existence of the neutron
What is meant by the activity of a source?
The number of nucleui which decay per second in a radioactive source, measured in Becquerels
What’s contamination?
When radioactive material is present in an object and will go on to decay and release ionsing radiation.
What’s irradiation?
When an object is exposed to ionising radiation
What three things must people who work with radiation take into consideration to reduce radiation risk?
Time, distance and shielding
Where does radon gas come from?
It is released from certain types of rock
What is background radiation?
Radiation which is always present in our environment to which we are constantly exposed
What do sieverts measure?
Dose of ionising radiation
What effect does ionising radiation have on cells?
Damages and kills them, and can cause cell mutation
Outline how carbon dating works
All living things contain C-14. When they die, the amount of C-14 begins to decrease as they don’t take any more in and it decays. By measuring the amount of C-14, we can estimate the age.
What is a radiation tracer?
A radioactive chemical put into the body which concentrates in a diseased or damaged part of the body. The radiation can be detected to help doctors diagnose the patient.
