### Chap 9 #6

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Would you find the longest wavelength needed to dissacociate a molecule by finding the bond energy and subsequently converting it to a wavelength?

-- Anonymous, April 19, 2000

Yes. Use table 13.5 (or any such table) to get the energy in the bond (remeber in table 13.5 this is the energy per mole, you need to convert) then use the formulas in chapter 12 to convert that energy into a wavelength.

good luck

-- Anonymous, April 20, 2000

What do I convert it to and how?

-- Anonymous, April 20, 2000

Okay, (re: #956266277) I used Avogadro's # and got an energy of 1.439e26. Then I used the equation: E = hv/wavelength and I got 1.381e-51 m. Converting this to nm, I got 1.381e-60. What did I do wrong?

-- Anonymous, April 20, 2000

You must take the energy, from table 13.5, convert it from MOLES to MOLECULES, then use the equation E=hc/lambda ---rearrange it so it is lambda (wavelength) = hc/E----and make sure that your constants are in the right units to cancel.

the last problem before my answer sounds like you didn't use the right sign on one of your exponents...check those!!!

-- Anonymous, April 20, 2000

how do you convert from kJ/mol to molecules for this problem? i have 339kJ/mol for the C-Cl bond and i don't know how to change it

-- Anonymous, April 20, 2000