TBR Chemistry chapter 2 example 2.25

[2010premed]

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Given that lambda 3-2 is 656 nm, which of the following is NOT true?

A. All Balmer series transitions are less than 800 nm
B. All Lyman series transitions are less than 400 nm.
C. The lowest energy Paschen transition is greater than 800 nm.
D. The highest energy Brackett transition is less than 800 nm

 

[SoftwareKevin]

Given that lambda 3-2 is 656 nm, which of the following is NOT true?

A. All Balmer series transitions are less than 800 nm
B. All Lyman series transitions are less than 400 nm.
C. The lowest energy Paschen transition is greater than 800 nm.
D. The highest energy Brackett transition is less than 800 nm

Choice A makes sense: 3-2 is 656 nm. All balmers will be higher in energy and thus lower than 656nm
Choice B makes sense: 2-1 is higher energy than 3-2 and thus lower than 656nm. All lymans will be higher in energy and thus lower than 656nm
Choice C makes sense: 4-3 is lower in energy than 3-2 and thus greater in wavelength. 4-3 is the lowest energy paschen. It's wavelength will be greater than 656nm
Choice D: I really have no idea what the highest energy Brackett is off the top of my head. I do know that the lowest energy bracket will have a wavelength greater than the lowest energy paschen so the wavelength of the lowest energy brackett should be >> 656nm. I would pick Choice D because choices A-C make sense while Choice D doesn't necessarily make sense.

Maybe someone else can have a better explanation for why D may not be true

edit: modified to be more clear

 

[ilovemedi]

Do we need to know the exact wavelength ranges for each series for the MCAT? I feel like that's too much info we need to know for this example =/