Chemistry
posted by Wyatt .
When an electron makes a transition from the n=3 to the n=2 hydrogen
atom bohr orbit, the energy difference between these two orbits
(3.0x10^19 J) is given off in a photon of light. The relationship
...
between the energy of a photon and its wavelength is given by
E=hc/wavelength, where E is the energy of the photon J, h is planck’s
constant (6.626x10^34 J x s), and c is the speed of light (3.00x10^8 m/s)
Find the wavelength of light emitted by hydrogen atoms when an electron makes this transition.

All you need to do is to substitute the numbers in to E = hc/wavelength.
3 x 10^19 = 6.626 x 10^34 x 3 x 10^8/wavelength.
Solve for wavelength. 
the energy from radiation can be used to cause the rupture of chemicals bonds. a minimum energy of 495 kj/mol is required to break the oxygen oxygen bond in o2. what is the longest wavelength of radiation that possesses the necessary energy to break the bond?

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