TBR General Chemistry. Section II - Atomic Theory. Passage 10 #68

[c0mplex]

68. Which of the following transitions emits the SHORTEST wavelength of light?

I don't quite understand how i got the wrong answer. I narrowed the choices down to A or B right off the bat.
A.X1 v=1 to X0 V=0, where V is the vibrational energy level.
B.X1 V=0 to X0 V=0 where V is " "

I chose B but the answers said A was correct. My reasoning of the question is that it's asking "which of the following has the highest energy", since the shortest wavelength corresponds to highest energy. I also apply my knowledge of knowing that UV is higher in energy and shorter in wavelength when compared to IR.

From the passage I gather that vibrational energy is lost as IR as the electron relaxes to it's ground state, while the relaxation of the electron releases energy in the form of UV. IR is lower in energy than UV. If energy is lost in the form of IR photons due to vibrational energy, wouldn't a lower energy photon be emitted? Therefore, the less energy lost through vibrational energy (IR) would result in the greatest energy lost in the form of a UV photon.

I might be misunderstanding the way the answers are presented (V=0 v=1) or the concept altogether. Please help.
Thanks in advance.
Tad

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[whiteshadodw]

68. Which of the following transitions emits the SHORTEST wavelength of light?

I don't quite understand how i got the wrong answer. I narrowed the choices down to A or B right off the bat.
A.X1 v=1 to X0 V=0, where V is the vibrational energy level.
B.X1 V=0 to X0 V=0 where V is " "

I chose B but the answers said A was correct. My reasoning of the question is that it's asking "which of the following has the highest energy", since the shortest wavelength corresponds to highest energy. I also apply my knowledge of knowing that UV is higher in energy and shorter in wavelength when compared to IR.

From the passage I gather that vibrational energy is lost as IR as the electron relaxes to it's ground state, while the relaxation of the electron releases energy in the form of UV. IR is lower in energy than UV. If energy is lost in the form of IR photons due to vibrational energy, wouldn't a lower energy photon be emitted? Therefore, the less energy lost through vibrational energy (IR) would result in the greatest energy lost in the form of a UV photon.

I might be misunderstanding the way the answers are presented (V=0 v=1) or the concept altogether. Please help.
Thanks in advance.
Tad

V1 refers to the vibrational energy level, and V1 - V0 is the difference in vibrational energy levels. since they both end up at X0 and V=0 then all that matters is which one started off with more energy. they both start off at X1, however in answer choice A you start off at V=1 so you have a little extra energy stored as vibrational energy.

so the complete energy change

A) (X1-X0)+(V1-V0) = energy
B) (X1-X0)+(V0-V0) = (X1-X0) = energy