R6 - Radioactivity Flashcards
What is at the centre of every atom?
A nucleus
What does the nucleus contain?
Protons and neutrons - they make up most of the mass of the atom but take up virtually no space
What charge are electrons?
Negatively charged - very small
What do electrons do?
Move around the outsize of the atom - there path takes up a lot of space giving the atom its overall size
What do the number of protons equal?
The atomic number
What do the protons and neutrons equal to?
The mass number
What are isotopes?
Atoms with the same number of protons but different number of neutrons
What are the two isotopes of carbon?
Carbon-12 and Carbon-14 (Carbon-14 has two more neutrons than ‘normal’ Carbon-12)
What number do the top and bottom numbers of an element represent (when drawing an isotope)
Top - mass number
Bottom - atomic number
Usually each element has one or two stable isotopes. What are the other isotopes?
Unstable - they tend to be radioactive so decays and emits radiation (eg Carbon-14)
What kind of process In radioactive decay?
A random process - each nucleus decays spontaneously and is completely unaffected by physical conditions like temperature
What does a nucleus split into when it decays?
Three types of radiation - alpha, beta and gamma - in the process the nucleus often changes into a new element
Give examples of background radiation
- Rocks/Soil/Food/Air
- Cosmic rays
- Fallout from nuclear explosions
- Nuclear waste
