Radioactivity Flashcards
What is radioactivity?
Radioactivity is the spontaneous breaking of unstable nuclei of an atom with the emission of one or more types of radiation.
What is a radioisotope?
A radioisotope is a radioactive isotope.
Describe:
- The structure of an alpha particle.
- What it’s represented as.
- How it’s created.
- The strength / danger it has.
- An example.
- Groups of 2 protons and neutrons (same as helium atom).
- Represented as He.
- Throw out of the nucleus of a radioactive element as it changes to a more stable nucleus.
- Least penetrating/weak.
- Example — Americium241 used in smoke detectors.
Describe:
- The structure of an beta particle.
- How it’s created.
- The strength / danger it has.
- An example.
- They’re electrons.
- The neutrons in an unstable atom change into protons and electrons and electrons ejected from the nucleus.
- More penetrating / medium / moderate.
- Example — carbon 14 used in carbon dating.
Describe:
- How it gamma radiation travels.
- If it has a high or low electromagnetic radiation level.
- How it’s created.
- The strength / danger it has.
- An example.
- Travels in waves.
- It has a high electromagnetic radiation level.
- It’s created when an unstable nucleus emits it, in order to lose surplus energy.
- Most dangerous / high.
- Example — Cobalt 60 which is used in curing cancer.
What is half-life?
The half-life of an element is the time taken for half of the nuclei in any given sample to decay.
Distinguish between a chemical reaction and a nuclear reaction.
- There is no new element formed / There is a new element formed.
- There is no release of nuclear radiation / There is a release of nuclear radiation.
- There are chemical bonds broken and formed / There are no bonds breaking or forming.
What is a device used to detect radiation?
A Geiger-Muller tube
Explain how alpha radiation takes place relating to nuclear reactions.
When an atom loses an alpha particle, it changes into an atom two places before it on the periodic table and the mass number decreases by 4.
What change occurs in an atom when beta decay occurs?
When an atom loses a beta particle, it changes by turning into the element before it on the periodic table and the mass number stays the same.
How is the rate of decay measured?
It’s measured by half-life.
What is an isotope?
An isotope is when atoms of the same element have different numbers of neutrons.
Name the three types of radiation.
- Alpha
- Beta
- Gamma
What is carbon dating?
Carbon dating is a scientific method of determining the age of an artefact.
What are the ionising ability of each of the types of particles?
- Alpha — strong
- Beta — moderate
- Gamma — weak
