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    I thought beta minus is where a neutron -> proton

    So surely there would be too many neutrons and vice versa for beta +
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    Also for fusion and fission do they both have a decrease in mass?

    Which is the mass defect

    E= mc^2 so energy is released?
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    Can someone explain ci)
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    (Original post by Super199)
    I thought beta minus is where a neutron -> proton

    So surely there would be too many neutrons and vice versa for beta +
    Beta minus is neutron -> proton, it's where there are too many neutrons

    Beta plus is proton -> neutron, it's where there are too many protons


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    (Original post by Super199)
    Also for fusion and fission do they both have a decrease in mass?

    Which is the mass defect

    E= mc^2 so energy is released?
    I believe fusion is an increase in mass while fission is a decrease, not sure though


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    (Original post by Super199)
    Name:  Fission help.jpg
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    Can someone explain ci)
    Calculate the mass defect and use e=mc^2


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    (Original post by Super199)
    I thought beta minus is where a neutron -> proton

    So surely there would be too many neutrons and vice versa for beta +
    Just remember conservation of charge

    If neutron -> proton, electron must be released to keep charge neutral (beta minus)

    If proton -> neutron, positron must be released to keep charge positive (beta plus)




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    (Original post by Kyx)
    Beta minus is neutron -> proton, it's where there are too many neutrons

    Beta plus is proton -> neutron, it's where there are too many protons


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    So the thing is wrong?
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    (Original post by Kyx)
    Calculate the mass defect and use e=mc^2


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    How though? Thats what I did for ii
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    (Original post by Super199)
    So the thing is wrong?
    Yes


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    b ii) and c i) are essentially the same question but with different values for the data

    b ii) is for a single atom, c i) is for 0.001 kg. you have to multiply the answer for b ii) by something


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    (Original post by Super199)
    How though? Thats what I did for ii
    Calculate how many uranium atoms are needed to make 0.001 kg. multiply that by your answer to b ii)


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    (Original post by Kyx)
    Calculate how many uranium atoms are needed to make 0.001 kg. multiply that by your answer to b ii)


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    Nah surely not.
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    (Original post by Super199)
    Nah surely not.
    I think so
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    (Original post by Kyx)
    I think so
    What numbers have you used?
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    (Original post by Super199)
    What numbers have you used?
    I'll just do the question now
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    (Original post by Super199)
    What numbers have you used?
    I got the answer to part b ii) correct.

    Then I converted 0.001 kg to u to get 6.02 x 10^23

    I divided this by the mass (in u) of the original uranium atom to get 2.55 x 10^21

    This multiplied by the answer to b ii) gives 7.65x10^10
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    (Original post by Kyx)
    I got the answer to part b ii) correct.

    Then I converted 0.001 kg to u to get 6.02 x 10^23

    I divided this by the mass (in u) of the original uranium atom to get 2.55 x 10^21

    This multiplied by the answer to b ii) gives 7.65x10^10
    Wait what numbers did you use here?

    6.02 * 10^23 and what else?
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    (Original post by Super199)
    Wait what numbers did you use here?

    6.02 * 10^23 and what else?
    236.053
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    (Original post by Kyx)
    236.053
    So I now get the workings, but I'm actually struggling to understand what's going on.

    Like do you mind explaining each step?
 
 
 
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