Calculate the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from n=5 to n=1 in J.

Answer 1

dE = 2.180E-18[1/(n1)^2 - (1/(n2)^2]

n1 = 1 and 1^2 = 1
n2 = 5 and 5^2 = 25