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Homework Help: Use the density of the liquid to estimate the radius of a neon atom.

  1. May 3, 2012 #1
    1. The problem statement, all variables and given/known data

    Neon is a monatomic gas;
    Density = 0.900 kg.m-3
    Pressure = 1 atm
    Temperature = 273K.
    Density of liquid neon = 1207 kg.m-3

    (i) Calculate the volume occupied by one gram mole of neon at a temperature of 273 K and a pressure of 1 atm.

    (ii) Determine the atomic weight of neon.

    (iii) Calculate the RMS speed of a neon atom at 273 K.

    (iv) Use the density of the liquid to estimate the radius of a neon atom.

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    2. The attempt at a solution

    i) V = nRT/P = 0.0224m3

    ii) n= m/M ∴ m = nM = 1x10 = 10g = 0.01kg

    iii) VRMS = √(3RT/M) = 824.98ms-1

    iv) third-root(liquid density/mass) = 49.42m <-- Bit big for an atom :s

    I am stuck on part iv) however I may have made a mistake further up so I have included the whole question and my working. Please help.
     
  2. jcsd
  3. May 3, 2012 #2
    A mole of neon occupies the volume you calculated.
     
  4. May 3, 2012 #3

    dextercioby

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    Homework Helper

    How many atoms of neon can one find in 1000 liters/1cubic meter of liquid neon ?
     
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