What happens in ionisation?
Radiation causes nuclear fission between between atoms
Radiation can knock out electrons in atoms so they become charged (ions) as they lose an electron
Half life:
half the time it takes for all nuclei in a radioactive sample to decay
half the time it takes for a radioactive sample to decay
the time taken for half the number of nuclei in a radioactive sample to decay
the time taken for half of the radioactive sample to decay
Half life is unpredictable yet we can predict how much will decay
Half life isn't random; it can be predicted when a sample will decay
Which are uses of radiation?
X-rays and killing cancers
Preserving food i.e killing its bacteria
Sterilising medical equipment
Preserving water
Powering houses
Carbon/ uranium dating
Thickness monitoring
Radioactive trackers for environmental and medical use
Smoke detectors
Powering heat
Beta radiation is:
an electron
a neutron
a ray
Beta radiation has ...
a -1 charge
a +2 charge
Alpha radiation has:
a +2 charge with 2 protons and 2 neutrons
a -1 charge because it is an electron
no mass because it is a ray
Gamma rays occur when a nucleus has too many neutrons compared to protons so a neutron changes to a proton (and a B particle)
Beta rays occur when a nucleus has too many neutrons compared to protons so a neutron changes to a proton (and a B particle)
Gamma rays would be emitted after alpha and/or beta particles
The most ionising (turning atoms into ions) radiation is
Gamma
Alpha
Beta
The least ionising* radiation is: * = Ionising: turning atoms into charged particles/ ions
Gamma is:
the least ionising form of radiation
the most ionising form of radiation
the least penetrating form of radiation
the most penetrating form of radiation
Alpha radiation is
the least ionising
the most ionising
the least penetrating
the most penetrating
Beta radiation is
in between alpha and gamma
Which is the odd one out?
An alpha particle is a helium nucleus
Gamma rays are the least ionising because
they are a ray and tend to pass through atoms rather than collide with them
they move around atoms and don't collide with them
Ionisation happens when particles (alpha or beta) collide with atoms, knocking out electrons, meaning they are now charged (ions).
Gamma rays are the most ionising.
Alpha particles are quite large (and slow)
Since alpha particles are quite large, this means they struggle to pass through paper or more then 5mm of air as they are too big to do so
Since alpha particles are quite large, they are more likely to collide with atoms and knock out their electrons
