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Homework Help: Nuclear Chemistry

  1. May 21, 2010 #1
    1. The problem statement, all variables and given/known data
    Consider 238U which undergoes natural radioactive decay to form thorium-234
    a)What is the activity, in curies, of 1.00 mg of U-238?
    B)What is the energy in kilojoules associated wuth the decay of 1.00 mg of 238U? The nuvlear mass of throium-235 is 234.0437

    2. Relevant equations



    3. The attempt at a solution
    A0
    0.693/(1.62*105)
    =4.27*10-6 j/k
    1*10-3*(1/238 g)*(6.022*1023/1 mol)
    =2.53*108
    my teacher marked this wrong, i dont know why!

    B)E=0.0449(9*1010)
    m=(234.0437+4.00150)-238=239.93558
     
  2. jcsd
  3. May 21, 2010 #2

    Borek

    User Avatar

    Staff: Mentor

    You expect us to guess what you did and what are these numbers?

    What if I will tell you that 1.521211? Does it make any sense without context?

    --
    methods
     
  4. May 21, 2010 #3
    Agreed; your answers don't even have units.
     
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