Radioactive decay Flashcards
Gamma radiation can be significantly reduced by…
lead
What form of radiation is emitted by nuclei with too many neutrons?
Beta
Gamma radiation is…
an electromagnetic wave
Which form of radiation has the highest ionising power?
Alpha
What causes an atom’s nucleus to become unstable?
Too many or too few neutrons in the nucleus
What is the activity of a source that emits 1,200 particles per minute?
20Bq
Uranium 238 emits an alpha particle to become what nucleus?
Thorium-234
alpha decay reduces the mass number by 4
An alpha particle is…
a helium nucleus
Which type of radiation can reach the furthest?
Gamma
What fraction of a radioisotope has decayed after two half-lives? - Higher
Three quarters of a radioisotope has decayed after two half-lives