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How many electrons does the atom have?

  1. Sep 9, 2015 #1
    1. The problem statement, all variables and given/known data
    A neutral atom is known to have a nucleus with a positive charge of 2.4 x10-12 C. How many electrons does the atom have?
    2. Relevant equations
    q=Ne

    3. The attempt at a solution
    None
     
  2. jcsd
  3. Sep 9, 2015 #2
    What have you tried? Where are you stuck?
     
  4. Sep 9, 2015 #3
    I tried finding out the amount of protons by multiplying 2.4 x 10^ -12 C by the amount of electrons in a coulomb 6.25 x 10^18. But then I got confused. So I would like to know how to get the answer and why that is the answer. Also I know the solution but not how to get there, the solution is 1.5 x107 electrons
     
  5. Sep 9, 2015 #4
    What does it mean that the atom is neutral?Let's start there.
    Also,in case you aren't aware,the charge of the electron(e) is a given.
     
  6. Sep 9, 2015 #5
    That means the electrons and protons balance each other out. Or in other words the whole atom has a neutral charge.
     
  7. Sep 9, 2015 #6
    What information about the electrons can you gain from what you just said?
     
  8. Sep 9, 2015 #7
    That the electrons and protons will be equal in amount or charge?
     
  9. Sep 9, 2015 #8
    Great!Can you calculate the number of electrons now?
     
  10. Sep 9, 2015 #9

    SteamKing

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    Are you sure the positive charge is 2.4×10-12 Coulombs? That's a lotta protons for one atom!

    https://en.wikipedia.org/wiki/Proton
     
  11. Sep 9, 2015 #10
    1.5 x 10^7 electrons. Thank you so much I get it now. :D
     
  12. Sep 9, 2015 #11

    SteamKing

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    You've just calculated a meaningless number. Which atom has 15 million electrons orbiting the nucleus???

    Hint: the natural elements have from 1 to 92 electrons per atom.
     
  13. Sep 9, 2015 #12
    Well that's true,but I guess what matters is he understood how to get there.
     
  14. Sep 9, 2015 #13

    Bystander

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    Does the original problem statement maybe have a "μ" preceding the "C"? As in "micro-coulomb?"
     
  15. Sep 9, 2015 #14

    SteamKing

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    Yeah, but the physics student should be aware of when he is calculating a reasonable result and when he is calculating nonsense. :wink:
     
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