radiation Flashcards
a word to describe decay
random
how can an atom become more stable overtime
by randomly (spontaneously) emitting ionising radiation
what are the three types of radiation
gamma
alpha
beta
what does alpha radiation release
helium nuclei
what does beta radiation release
electrons
what is gamma radiation
a high-energy electromagnetic wave
what are the three main ways of detecting radioactive activity
cloud chamber
photographic film
geiger counter
what is a cloud chamber
a container full of air containing alcohol vapour
The alcohol vapour condenses on the ionised air molecules, showing the trail of radiation.
what is photographic film
a bright stop appears whenever the radiation hits the film
examples of things that emit radiation
rocks
the sun
radon
food
what does an alpha particle contain
2 protons
2 neutrons
what are the properties of alpha
does alot of damage but stopped by small amounts of matter
what are the properties of gamma
weakly ionising
less damage but stopped by larger amounts of mass
what are the properties of beta
middle ionising
high energy electrons
pass through paper but not foil
how does a smoke detector work
A radioactive material fires alpha particles at a smoke detector.
If there is smoke between the radioactive material and the smoke detector, then fewer alpha particles will reach the d
what can beta radiation be used for
paper production
what can gamma radiation be used for`
medical sterilization
what is nuclear fission
splits 1 nucleus into 2 or more smaller nuclei.
hat is the process of nuxlear fusion
A neutron collides with a large nucleus and is absorbed. This creates an unstable nucleus.
This nucleus then splits into fragments. This releases large amounts of energy and more neutrons. These neutrons can then collide with other nuclei.
what creates an unstable nucleus
A neutron collides with a large nucleus and is absorbed.
what happens if nuclear fission is not controlled
the rate of nuclear fission speeds up
a chain reaction where each stage of fission produces more and more energy
what is nuclear fusion
fuses (joins) 2 smaller nuclei to create 1 larger nucleus. Creating this larger nucleus releases energy.
what form of decay doesnt create a new element
gamma
what rules must be followed when writing decay equations
the sum of the atomic numbers must be equal
the sum of the mass numbers must also be equal
how many protons and neutrons are lost in alpha decay
2 pro
2 neut
what stays the same in nuclear fission
num of protons
how many nucleons are released in nuc fission
4
what happens in beta decay - equ
1 electron is carried away nitrogen is formed
number of nucleons stays the same
what happens in gamma rays
nothing
what occurs in beta decay
a neutron in the nucleus decays to form a proton and an electron - which is then ejected
what occurs in alpha decay
it looses 2 protons so it becomes a new element
what occurs in gamma decay
nucleus relaxes and goes into a state of lower energy
what is half life
the average time taken for the number of radioactive nuclei to halve.
what is the activity of a radio active substance measured in
Becquerels (Bq)
what are ions
particles that become charged by gaining or losing electrons.
what is bad abt ions
they damage cells
what are the safety precautions of radiation
storage
reduced exposure
usage
handling
what is contamination
radioactive substances occur from inside something. Irradiation is when something is exposed to radiation on its outside.
what is irradiation
When something is exposed to radiation on its outside.
what are the different types of contamination
beta
alpha
gamma
what is beta contamination
not very harmful and can pass out the bdy
what is alpha contamination
most dangerous
cant pass through the body
cancer
what is gamma contamination
least harmful
most penetrative
