Achieve hw #2: question #12

[Megan McKenna Dis1A]

Hi! I wasn't sure how to get this question regarding electron affinity started. What equation should I be using to calculate electron affinity?

[Chelsea Greene 1L]

To start this problem we need to find the difference in energy between the photons that are bombarding the element and the energy of the ejected electron. We can use E=hc/lamda to find the energy of the photons. Just make sure as you go through the problem you pay attention to the units and unit conversion!

[Holland Smith 3C]

I was able to get the first part done, but am having some trouble on part 2. So far, I have used the eV from part 1, converted it into kJ, and have since been playing around with different uses of Avogadro's number (either subtracting or dividing) and am still not getting any closer.

[Bailey Wallace 3A]

Hello! For this problem I got up to the point where you are supposed to convert energy to electron volts but I am struggling with the conversion :( Can someone give me an example?

[Hailey Sarmiento 3E]

Hi! You can calculate the electron affinity by finding the energy of the photon with the wavelength given (E = hc/lambda), converting that to eV/atom, and subtracting the energy of the electrons they gave you in the question. For the second part of the question you just need to convert the answer you got in part 1 to kJ/mol with the ratios 1.602e-19J/1eV, 1000J/kJ, and 6.022e23atoms/1mol.

[Nico Towfighian 3L]

TO do this problem, you are given the emitted energy, and the incident radiation wavelength. THe problem statement says electron affinity is defined as incident radiation energy subtracted by emitted energy. You are given the emitted energy so just solve for the radiation energy by using wavelength, (l= hc/E) then convert given value to electron volts and there's your answer for part A, then for part B convert it back to joules (kilojoules) then multiply it by avacadros number.