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The energy required to split apart hydrogen bromide according to the equation is 6.01 × 10-19 J/molecule. HBr(g) → H(g) + Br(g) Calculate the wavelength (m) of the photon that can dissociate hydrogen bromide. Express answer in scientific notation.
This is sort of a blur to me since it's been quite some time, but I think you use: \[E = hf = \frac{ hc }{ \lambda }\] where the greek symbol, lambda, represents wavelength.
I think Abb0t is right on the money again. I believe h is Planck's constant in this equation: http://en.wikipedia.org/wiki/Planck%27s_constant