1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Calculating the diameter of a polonium atom

  1. Jul 5, 2010 #1
    1. The problem statement, all variables and given/known data
    Polonium has a simple cubic structure at room temperature. Given that the mass density of solid [tex]^{209}_{84}[/tex]Po is 9.2gcm^-3 , calculate the diameter.

    3. The attempt at a solution

    Volume = mass/density = 209/ 9.2 = 22.7 cm^3

    1 mole = 6.02 x10^23 mol^-1

    22.7 / 6.02x10^23 = 3.77 x10^-23 cm

    volume = 4/3 (pi) r^3

    So diameter is 4.16x10^-10 m ?

    Is this correct? I have no answers to refer to. Thank you.
  2. jcsd
  3. Jul 5, 2010 #2
    It looks absolutely correct to me.
    Other than the third step where you (accidentally?) put "cm" instead of "cm^3"
    But the answer I think is right.

    Also, angstroms would be a more convenient unit, as it is 10^(-10)m.
    so the answer could be:
    4.16 angstroms
  4. Jul 5, 2010 #3
    How would you stack balls so that they fill the whole space?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook