Question

What is the frequency of light with an energy of 124 kJ/mol?

Answer 1

Answer: = 3.11 x 10^14 s^-1

Explanation:

Use the formula E = hv

This formula uses the assumption that the unit for energy is in Joules/photon.

124 kJ = 124000J

To get 124000J/mol into a unit of J/photons, we need to divide by the number of photons in a mole, which is 6.022 x 10^23.

And thus, we need

124000/6.022 x 10^23 = 2.06 x 10^-19J/photon

We can plug it in to E = hv by

2.06 x 10^-19J = (6.63 x 10^-34 J s)(v) Isolate v by

v = (2.06 x 10^-19J)/(6.63 x 10^-34 J s)

= 3.11 x 10^14 s^-1