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Post Assement audio visual

Posted: Sat Oct 24, 2020 11:26 pm
by Bailey Giovanoli 1L
On the post assessment quiz for the audio visual module on the photoelectric effect you are asked to find the energy required to remove an electron from one sodium atom. You are given the work function to be 150.6 kJ/mol. Isn’t the work function the same as the energy required to remove an electron? This is what I thought, however 1.506 x 10^5 is not the answer. The other answer options are:
2.501 x 10^-22
2.501 x 10^-19
9.069 x 10^28
I had a feeling 1.506 x 10^5 was far to large, so I’m assuming so is the last answer option. I do not know how to find the other two as an answer however, can someone walk me through the process?

Re: Post Assement audio visual

Posted: Sat Oct 24, 2020 11:34 pm
by Eliana Witham 2H
I may be wrong, but I believe the answer is middle option. You are correct that the work function is the energy required to remove an electron. You have to convert kJ/mol to J/photon. In order to do this, you can use conversion factors to convert kJ to J, then multiply this by (1 mol/ 6.02x10^23 photons) to get the correct units.

Re: Post Assement audio visual

Posted: Sat Oct 24, 2020 11:38 pm
by Bailey Giovanoli 1L
Oh my gosh! Of course. I don’t know how I could forget that step. Thank you so much:)

Re: Post Assement audio visual

Posted: Sun Oct 25, 2020 9:12 pm
by Andy Hernandez
A tip for anyone seeing this. I kept getting the wrong answer bc i didn't put parantheses around (1mol/ Avogdro's constant) so make sure to do that. I was stuck on this problem for thirty minutes bc of this :(