1) the spectrum of lithium has a red line of 670.8 nanometers. (remember 1 m = 1 x 109 nm) a. convert the nanometer to meter using dimensional analysis. b. calculate the frequency of the wave. c. calculate the energy of a photon with this wavelength.

E = ħc / λ
 ħ = plancks constant = 6.626x10^-34 Js
c = speed of light = 2.999x10^8 m/s
λ = wavelength of light = 670.8x10^-9 m
 
E = (6.626x10^-34 Js) x (2.999x10^8 m/s) x (1 / 670.8x10^-9 m)
E = 2.962x10^-19 J

3x10^8 / (670.8 * 10^-9) =4.47x10^14 Hz
 
4.47x10^14 Hz multiplied by plank's constant = 2.9634x10^-19

Thank you for posting your question here at . I hope the answer will help you. Feel free to ask more questions here.

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.