Nuclear physics Flashcards
What is an alpha particle and what charge does it have?
It’s a helium nucleus- 2 protons and 2 neutrons- with a positive charge of +2
What is a beta particle and what charge does it have?
It’s a fast moving electron with a negative charge of -1
What is a gamma ray?
An electromagnetic wave
How do you work out alpha decay?
The mass number decreases by 4 and the atomic number decreases by 2
How do you work out beta decay?
The mass number stays the same and the atomic number increases by 1
Why doesn’t gamma decay have an equation?
Because it’s an electromagnetic wave that occurs as a consequence of alpha or beta decay
What is the radiation that radioactive substances emit?
Ionising radiation, meaning that it knocks electrons off them, making them chemically reactive
What is a danger of ionising radiation?
It may mutate body cells, increasing risk of cancer
What is radiation measured in?
Sieverts (Sv) or millisieverts (mSv)
What is the unit of activity?
Becquerels (Bq)
What is nuclear fission?
The splitting of a nucleus; mostly, it occurs when a nucleus is hit by a neutron and it splits into two smaller nuclei
What is a fission event?
When several neutrons are released, which can cause other fissionable nuclei to split. This then produces a chain reaction of fission events
What is nuclear fusion?
The joining of two atomic nuclei to form a larger one
Why do nuclei emit radiation?
Because they want to become stable (balanced)
What is the process of radioactive decay?
When an unstable atomic nucleus loses energy to make itself more stable by emitting radiation such as an alpha particle, beta particle or gamma ray
