### Chap 9 Question 6

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Im still haveing trouble with #6 from Chap 9...the id # is 956341392..what do they want...

-- Anonymous, April 21, 2000

As with the questions on problem 6 earlier, you have to find the energy associated with the O-O bond (use table 13.5) then convert that energy from kJ/mole to J/molecule (use 1000 J per kJ and avagadro's number) then use the formulas from ch 12 Lambda(wavelength)=h(planks constant) x c (the speed of light) / energy (the one you just converted to J/molecule) and then change your answer from meters (what you get from the dimensional analysis (all other units cancel and you are left with an answer in meters) to nanometers (1 x 10^-9 m) because CALM wants the answer in nm!

Good luck!

-- Anonymous, April 21, 2000

Ok I got to thinking maybe you wanted to know more of the theory behind the question???

In every bond there is some energy....how much depends on the bond length, the atoms etc. If you input enough energy into the molecule (enough to overcome the energy in the bond) then you can actually break the bond. What the question here is asking, if you shoot the molecule with light inparting energy to the molecule, what wavelength would the light have to be to give the molecule enough energy to break the bond? So to answer, we need to figure how much energy is in one molecule, the table gives us the energy in a mole--so we convert that. Then we can use that energy and some constants (see previous message) to figure out what wavelength of light would give us the energy needed to break the O-O bond.

Terri

-- Anonymous, April 21, 2000

Thanks Terri....it worked.

-- Anonymous, April 21, 2000