Radioactive Decay Flashcards
(10 cards)
What is radioactive decay?
The process by which an unstable atomic nucleus loses energy by emitting radiation.
What are the three main types of ionising radiation?
Alpha (α), beta (β), and gamma (γ) radiation.
What is an alpha particle?
A particle made of 2 protons and 2 neutrons (same as a helium nucleus).
What is a beta particle?
A high-speed electron emitted from the nucleus when a neutron turns into a proton.
What is gamma radiation?
electromagnetic radiation released from the nucleus with no mass or charge.
What is meant by the ‘half-life’ of a radioactive isotope?
The time it takes for half of the radioactive nuclei in a sample to decay.
What material can stop alpha particles?
A sheet of paper or human skin.
What is the change in atomic and mass number during alpha decay?
Mass number decreases by 4; atomic number decreases by 2.
What is the change in atomic number during beta decay?
Atomic number increases by 1; mass number stays the same.
Why is radioactive decay dangerous to living cells?
It can ionise atoms in cells, potentially causing damage or cancer.
