Section 7 Atomic Physics Flashcards
Relative Charge of proton neutron and electron
+1
0
-1
How are alpha particles charged
Positively charged
How to find proton number
The number of protons in an atoms nucleus
The nucleon number equation
The number of protons + the number of neutrons
What are isotopes
Same number of proton different neutron
What is radioactive decay
The process in which unstable nuclei change to become more stable by emitting ionising radiation
Name the 3 emissions
Alpha
Beta
Gamma
Each emission penetrating and ionising power
Alpha - poor | strong
Beta - moderate | moderate
Gamma - strong | weak
What does lead. Do
Absorbs all types of radioactive emissions
How does each emission travel through air and other things
Alpha - few cm and absorbed by a sheet of paper
Beta - few meters in air and are absorbed by thin aluminum
Gamma - long distance through are and absorbed by thick sheets of lead or meters of concrete
What happens in alpha decay
Number of protons and neutrons decrease
What does beta decay do
Number of protons increase by one
What detects radioactive particle
Geiger muller detectors
Where are alpha and beta particles deflected
In electric and magnetic fields
What is nuclear fission
Splitting a large and unstable nucleus
What is nuclear fusion
Joining small nuclei
Why do fission and fusion both release energy
Total mass before fission or fusion is higher than the total mass after. The extra mass is converted to energy and released
Why are alpha particles more ionising than beta particles
Aloha particles have a greater mass giving them more energy in their kinetic energy stores and have more charge than beta particles
What is half life
The time taken for the number of nuclei of a radioactive isotope in a sample to halve
What is beta emitters used for
Thickness gauges to help control thickness
What are alpha emitters used for
Smoke detectors and ionise air particles in the smoke causing a current to flow
What effect can a low dose of radiation have on cells
Minor damage to cells
Cancer
Cell mutation
3 main sources of background radiation
Food and drink,
building materials,
Cosmic rays
