What is the wavelength in Angstrom of the photon of light absorbed when the electron of the hydrogen atom is promoted from n=2 to n=6.?

1/λ = 1.097x10^7 m^-1 (1/nf^2 - 1/ni^2)

1/λ = 1.097x10^7 m^-1 (1/6^2 - 1/2^2)

1/λ = 1.097x10^7 m^-1 (0.0278 - 0.25)

1/λ = 1.097x10^7 m^-1 (-0.2195) = -2.41x10^6 m^-1

λ = 4.15x10^-7 m = 4150 Aº

Or done another way

∆E = -2.179x10^-18 J (1/nf^2 - 1/ni^2) = -2.179x10^-18 J (-0.2195) =

4.78x10^-19 J

E = hc/λ

λ = hc/E = 6.626x10^-34 J-sec x 3x10^8 m sec^-1/4.78x10^-19 J = 4.159x10^-7 m = 4158 Aº