Question

Help!! what is the energy per mole of photons having a frequency of 5.38*10^13 Hz?

I know that E=hv and h=6.63e-34 and that avogadros number is 6.02e23 but when i solved it none of the multiple choice answers matched mine!

Answer 1

First you want to set up your equation and plug in the numbers.
Ephoton=h*v where h is Planck's constant (6.63e-34) and v is frequency (which is given in the problem)
now you should have an equation that looks like this:
Ephoton=6.63e-34*5.38e13
Once you solve the above problem you will have the Energy of just one photon. Now you need to find the Energy of a mole of photons. In order to do that you need to multiply your answer by Avogadros number (6.02e23).
Now you should have an equation that looks like this:
Ephoton*6.02e23=Energy of one mole of photons.

If this doesn't make any sense try to watch this video that I found:
http://www.youtube.com/watch?v=M7UAPGD8ETU

Answer 2

thanks