atomic structure (paper 1) Flashcards
number of protons=?
number of electrons
3 main types of radiation
alpha
beta
gamma
what does the plum pudding model state?
an atom is made up of a sphere of positive charge with negative electrons spread throughout it
what is the atomic number
number of protons
what is the mass number
number of protons + neutrons
define the term isotope
an atom with the same number of protons but a different number of neutrons
what is gamma
EM wave
what is beta
fast moving particle
what is alpha
helium nucleus
count rate after n half-lives is equal to…
initial count rate/2n
2 main medical uses
medical tracers
cancer treatment
define fission
the splitting of an atoms nucleus into two smaller nuclei
define a chain reaction (fission)
when a fission event occurs more neutrons are given off which then go on to cause further fission events
define fusion
process of forcing 2 atoms’ nuclei together to form a single larger nucleus
how can nuclear fusion be made to happen?
by colliding particles at a very high speed.
where does fusion happen?
in stars where hydrogen fuses into helium
where does radon gas come from?
natural radioactive materials underground which then seep through the rocks into the air
what does radon gas emit?
alphas - so can be hazardous if breathed in
are alpha particles highly ionising?
yes
inside which part of a nuclear power station would molybdenum be produced?
nuclear station
define the term half-life
the average amount of time taken for an unstable nuclei to half
even though there’s a risk, doctors frequently use radioactive substances for medical diagnosis and treatments. Suggest why
benefit is greater than the risk
