fission and fusion and nuclear reactors Flashcards
what happens during fission
large nuclei break into smaller nuclei
what happens during fusion
small nuclei join together to produce larger nuclei
what is a typical fuel of fusion
hydrogen
is there an increase in mass in fission
no
is there an decrease in mass during fusion
yes
can fusion or fission be used in weapons, if so which one
yes, both
energy is released in fusion is generally
large
fusion is an energy source in
stars
energy is released in
both
can fission or fusion be used in weapons, if so which one
both
the core temperature of fission is generally
high ( 300ºC)
relative energy released in fission is
small
the electrostatic attraction must be overcome in
fusion
a typical fuel of fission is
uranium
fission requires ___ moving neutrons
slow
in which is there a decrease in mass and why
both
because some of the mass is converted into energy
nuclear fission is
a type of nuclear reaction that is used to release energy from large and unstable atoms by splitting them into smaller atoms
for fission to happen a ____ needs to collide into the nucleus
neutron
the type of energy released in fission is
kinetic energy
in nuclear fusion, 2 ____ nuclei collide at ____ speed and __ to create a larger and heavier nucleus
light
high
fuse
hydrogen nuclei fuse to form a
helium nucleus
the energy released in fission can be used to
heat water to make steam for turbines and generators
in fusion, is the mass heavier before they fuse or after
before
does fusion release a lot of energy
yes
have scientists found a way of using fusion to generate energy for us to use ?
no
because its expensive but mostly, the conditions needed are very high temperatures and pressures and we haven’t been able to create them without using more energy thsn the fusion would create
nuclear fission is used to
generate electricity in nuclear power stations
nuclear fusion releases ___ energy from a given mass of fuel and produces way ___ nuclear waste
more
less
fuel is unlimited for
fusion
conditions needed for fusion
the conditions needed are very high temperatures and pressures
what are the 2 types of fission
spontaneous fission
induced fission
products of fission
- 2 daughter nuclei
- 2 or 3 neutrons
when does induced fission happen
when a neutron is absorbed
when does spontaneous fission happen
on its own, no neutron needs to be absorbed
something that can undergo fission is called
fissile
___ neutrons are better at inducing fission than ___ ones
slow
fast
a chain reaction happens when
the released neutrons of one fission reaction collide with other atoms, which themselves then undergo fission.
in fission, the neutrons released carry ___ of the energy from the reaction.
most
in a nuclear reactor ( fission), the neutrons are __ ___ and transfer energy by ___
slowed down
heating
a chain reaction is stopped by
control rods
is radioactive decay a source of energy
yes
in uranium 235, when fission occurs, it produces___ neutrons, __ daughter nuclei and creates__ which is very ___ and falls apart.
2 or 3
2
Uranium 236
unstable
fusion is the energy source for
stars
a chain reaction can only be stopped if
it is in a nuclear reactor and you insert control rods
a control rod
absorbs neutrons
if a control rod is inserted fully, it
stops reactions altogether
raising the rods ____ the rate of fission because …
increases
fewer neutrons are absorbed
fission in a control rod is called
controlled fission
a moderator
slows down neutrons
the moderator is a material that
surrounds the fuel rods inside the reactor core and helps graphite heat up
