chemistry help please?

Question

in my chemistry homework, I am given for the H atom: E_n_ = -(21.79*10^-19 J)/n^2
E_ph_=(21.79*10^-19 J)/((n_L_^-2)-(n_U_^-2))

if it is transitioning from n=1 to n=2, what do the other things mean. How would you calculate the wavelength.

Thanks, I can not find the code for my ebook, so i dont have a book.

sorry I meant it goes from n=1 to n=4

Answer 1

Oh boy, I forgot chemistry already... I'm now into Physics...