posted by Liana .
What is the de Broglie wavelength in nm of a buckyball, (molecular formula C60), moving at speed 250 m/s?
I don't understand how you find the mass from the molecular formula C60.
The answer is 2.2*10^-3nm. I tried multiplying the mass of carbon by 60, but it didn't come out with the right answer.
You were half way there.
The molar mass of a buckyball is indeed 60 x 12 = 720 (you may need to use closer numbers than this from the periodic table) and that is for a mole of buckyballs. There are 6.02E23 buckyballs in a mole of buckyballs; therefore 1 buckyball has a mass of
720/6.02E23 = ?grams. You need to change that to kg. Now just plug that in and solve for wavelength. Remember the answer will be in meters and you will need to change that to nm. There are 1E9 nm in a m.