1. The problem statement, all variables and given/known data What values of n are involved in the transition that gives the rise to the emission of a 388-nm photon from hydrogen gas? 2. Relevant equations n=? wavelength = 388nm=3.88x10^-7 m R=1.097x10^7 m^-1 E= hc/ wavelength 3. The attempt at a solution E= hc/ wavelength=(6.63x10^-34)(3.00x10^8)/ (3.88x10^-7) = 5.13x10^-19 J = 3.206 eV En = -13.6eV / n^2 n = - square root of (13.6/En) = -square root of (13.6/3.206) = - square root of 4.24 = -2.06 n = 2 <- 1st excited state the answer is n=8 to n= 2. How would I know that it began from n=8 ?? Maybe there's an equation that I missed..