p2 help
Watch this threadPage 1 of 1
Skip to page:
exam crazy
Badges:
0
Rep:
?
You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
I'm getting really confused between nuclear fission and fusion, can someone just explain them briefly to me please?
0
reply
gallowsCalibra
Badges:
0
Rep:
?
You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report
#2
first you need to know that nuclear reactors use a reaction called nuclear fission. fission basically means splitting, and we're splitting a nucleus; hence the name nuclear fission. in nuclear reactors, uranium 325 and plutonium 239 are generally used as fuels, this is because they have big nuclei, and because they're so big they're easier to split- ESPECIALLY when they're hit by neutrons. when they're hit by neutrons, the nucleus first splits into two smaller nuclei, those of which are radioactive. following this, about two more neutrons are released, along with some energy. this causes a chain reaction. as more neutrons are released, they continue to split the new plutonium and uranium nuclei. this reaction has to be controlled in nuclear reactors so that they don't go too fast.
nuclear fusion is much simpler. it's basically when a large nucleus is formed from two smaller atomic nuclei. and obviously energy is released when this takes place, as per usual. this process is used by the sun and much smaller stars, as it allows them to release energy. the actual sequence of nuclear fusion reactions is really complicated, but overall hydrogen nuclei fuse to form helium nuclei. so, for example:
hydrogen-1 nuclei fuse with hydrogen -2 nuclei to form helium-3 nuclei.
i'm pretty sure that's all you need to know, (i am retaking p2 this year but i haven't bothered to revise it yet, this is just what i remember), but you should definitely read about it in the revision guide and answer questions on the topic for further help.
nuclear fusion is much simpler. it's basically when a large nucleus is formed from two smaller atomic nuclei. and obviously energy is released when this takes place, as per usual. this process is used by the sun and much smaller stars, as it allows them to release energy. the actual sequence of nuclear fusion reactions is really complicated, but overall hydrogen nuclei fuse to form helium nuclei. so, for example:
hydrogen-1 nuclei fuse with hydrogen -2 nuclei to form helium-3 nuclei.
i'm pretty sure that's all you need to know, (i am retaking p2 this year but i haven't bothered to revise it yet, this is just what i remember), but you should definitely read about it in the revision guide and answer questions on the topic for further help.
0
reply
nao123
Badges:
7
Rep:
?
You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report
#3
It's also worth remembering that nuclear fusion reactors aren't used as they are too impractical. You need to sustain really high temperatures (similar to the Sun's) to give the two nuclei enough kinetic energy to overcome the extremely strong electrostatic repulsion felt by both nuclei. This is due to the fact that both nuclei are positively charged. This means that nuclear fusion reactors aren't used as the energy you would put in would be far greater than the energy would gain from the reaction.
0
reply
X
Page 1 of 1
Skip to page:
Quick Reply
Back
to top
to top