The Hydrogen Spectrum & Energy Levels
BlackBoard Notes

======================= Photo - Click for a Larger Version =============================

======================= First Board Section =============================

• Measure λ's for visible lines of Hydrogen
• Calculate expected λ's and identify transitions producing the lines observed
• Do Not Move the Spectrometers!

• ---

• (If needed:) Lab Evaluations!
• On front bench
• Fill one in (out?)
• No name required
• Leave pages stapled together

======================= Second Board Section =============================

• Wavelength of each H-line:
  • Measure θ for each line, to 0.1°
  • Measure θ for Yellow line of sodium (λ_Na = 589.3 nm)
  • Calculate d from Na measurement:
    • mλ = dsinθ
  • Use this d to calculate λ_H for each hydrogen line observed
    • Calculate λ to 4 sig figs!

======================= Third Board Section =============================

1. Energy level diagram (Large and Neat!):
   • Drawing note for Jeff:
     • First draw horizontal lines for n = ∞ and n = 1
     • Label n = ∞ as "Ionization Level"
     • Fill in other levels by taking ½ of available space
     • Finish with vertical axis and transitions
     • Equations may run into the Fourth Board Section

    

    

2. Which transitions created each H-line observed? Be specific!
3. Turn off the H-bulb when finished measuring your angles!

======================= Fourth Board Section =============================

Spectrometer Alignment Notes: (Note that this section will be tight on space!)

• Move front of spectrometer left and right so zeroth order image is pink, not pink and blue!

  

• Move telescope by pushing the angle pointer, NOT the eyepiece!
• Rotate eyepiece to align crosshair parallel to spectral line.

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©	St. Lawrence University	Department of Physics

Revised: 12 Jun 24

Canton, NY 13617