# Calculate Longest & Shortest Wavelength?

A) Calculate the wavelength of light emitted with the longest possible wavelength.

B) Calculate the wavelength of light emitted with the shortest possible wavelength.

I’ve solved part B, but cannot solve part A. Any suggestions?

Part B [CORRECT]

V=13.14V so KE=13.14 eV

En=-13.6/(n^2)

E1= -13.6 eV

E= -13.6 eV + 13.14 eV

E= -0.45 eV

E2= -3.4 eV

E3= -1.5 eV

E4= -0.85 eV

E5= -0.544 eV

E6= -0.378 eV

E=E5-E1

E=(-0.544)-(-13.6)

E= 13.056eV * 1.6e-19 J

E= 2.089e-18 J

E=hc/λ

λ=hc/E

λ=(6.626e-34)*(3e8)/(2.089e-18)

λ= 9.52e-8 m

Attempt at Part A) [INCORRECT]

Longest wavelength is in Paschen series (n=3)

E=E4-E3

E=(-0.85)-(-1.5)

E= 0.65eV * 1.6e-19 J

E= 1.04e-19 J

E=hc/λ

λ=hc/E

λ=(6.626e-34)*(3e8)/(1.04e-19)

λ= 1.91e-6 m

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