# Chem.

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Three emission lines involving three energy levels in an atom occur at wavelengths x, 1.5x, and 3.0x nanometers. Which wavelength corresponds to the transition from the highest to the lowest of the three energy levels?

• Chem. - ,

delta E = hc/lambda. Going from the highest to the lowest energy level must involve the highest E. To have the highest E, lambda must be the ??

• Chem. - ,

is it the wavelength? I have no idea.

• Chem. - ,

C'mon now. You need to understand how to do this and this is a simple problem in logic. Here is the way the logic goes. Suppose we have an equation that is x = 5/y. Now, as y gets larger, x must get smaller. Try it. y = 1 then x = 5/1 = 5, right? y = 2, then x = 5/2 = 2.5 (x is smaller when y is larger), right? y = 5, then x = 5/5 = 1 (smaller than when y was larger). Now apply that same reasoning to
E = hc/lambda. h is a constant, c is a constant, the wavelength is the only variable. You want delta E to be the largest it can be because the transition is from the highest to the lowest level which means highest E. So lambda must be?? (smaller or larger are the only two choices and that dictates the answer of x, 1.5x or 3.0x.)