Physics: Atomic Structure Flashcards
What did J.J Thompson discover in 1904
Plum Pudding Model
What was the Plum Pudding
Atomic model where there was a massive blob of positive matter mixed with randomly spaced out electrons
What are Isotopes
Atoms with the same number of protons but different number of neutrons
What are Alpha Particles
Helium nuclei that don’t penetrate much material but are strongly ionising
What are Beta Particles
Fast moving electron released by the nucleus. They are moderately ionising and penetrating
What are gamma rays
EM waves with a Short wavelength that are deeply penetrating and weakly ionising
What does Alpha decay do
Decreases the Charge and Mass of the nucleus
What does Beta decay do
Increases the charge of the Nucleus
What do gamma rays do to the nucleus
Only get rid of excess energy
What is half-life
The time taken for the number of radioactive nuclei in an isotope to halve
What is activity measured in
Becquerels (Bq)
What is the risk of harm to body tissue from radiation measured in
Sieverts (Sv)
what is exposure to radiation called
Irradiation
what is radioactive particles getting into an object called
Contamination
what are the three risks of radiation
Tissue damage, cell mutation (cancer), radiation sickness
