Report Form for Computer Lab 6: Spectroscopy of simple atoms
Student’s Name: _________________________________________________
BU ID_________________________________________________________
Lab Section Day/Time/TF_________________________________________
Investigation 1: Lyman series
1. What is the asymptotic value of the light quantum energy, ΔElight, UV limit, for Lyman series in your plot for ΔElight,
UV limit versus N on page 8?
ΔElight, UV limit =________________
2. Write the formula that relates ΔElight to ΔE∞ and N (page 10):
3. What is the slope and the intersect value for your plot for ΔElight vs 1/n2 (page 11):
Slope = ____________;
Intersect value with ΔElight-axis= _________________
Investigation 2: Balmer series
1. What is the asymptotic limit of the spectral line energy in hydrogen for Balmer series in your plot for the light
quantum energy of the Balmer Series spectrum against the spectral line number (page 15):
ΔElight, UV limit =________________
2. Write the formula for (ΔEBalmer, ∞ –ΔEN,light) in terms of ΔELyman,∞ and n, where n=3,4,5….(page 17)
3. What is the slope and the intersect value for your plot for ΔElight vs 1/n2 for Balmer series (page 17):
Slope= ____________;
Intersect value with ΔElight-axis= _________________
Investigation 3: Bohr’s Interpretation of the spectral data
1. What are the energy asymptotic limits for each of the series listed in the table below (page 20)
Series
Lyman
Balmer
Paschen
Brackett
Pfund
Energy Asymptotic Limit (eV)
Copyright © 2006 Peter Garik ([email protected]). All rights reserved.
L6-2
Exploring quantum concepts in general chemistry
2. Specify below to which series belong the following lines:
a) λ=102.560nm ___________________; b) λ=7491.48nm ___________________;
Investigation 4: Spectral Analysis of Charged hydrogen –like atoms
Activity 1: He+
1. Based on your results for energy levels in He+:
a) estimate the lowest three energy levels of the He+ ion (page 30):
E1= __________eV;
E2=___________eV;
E3=_____________eV.
b) write an expression for the n-th atomic energy level for He+ (page 30):
E n, He+=
c) Using your formula for the atomic energy levels of He+ ion, find the initial and final energy levels of He+ when
the following spectral lines are emitted (page 31):
Wavelength, λ (nm)
ninitial
nfinal
30.388
121.553
541.415
Activity 2: Li2+
1. Based on your results for energy levels in Li2+:
a) estimate the lowest two energy levels of the Li2+ ion (page 33):
E1= __________eV;
E2=___________eV;
b) write an expression for the n-th atomic energy level for Li2+ (page 33):
E n, Li2+=_______________
c) What is the energy value for the second excited state in Li2+? (page 33):
E3= _______________eV
d) Write the relationship between the energy levels of H and the energy levels of Li2+ (page 34):
Copyright © 2006 Peter Garik ([email protected]). All rights reserved.
L6-3
Report on Lab 6: Spectroscopy of simple atoms
e) Using your formula for the atomic energy levels of Li2+ ion, write in the table below the initial and final energy
levels of Li2+ when the following spectral lines are emitted (page 34):
Wavelength, λ (nm)
nfinal
ninitial
11.396
415.635
569.779
656.347
Activity 3: Be3+
1. Based on your results for energy levels in Be3+:
a) what are the energy for the ground state and for the fist and second excited states in Be3+ ion (page 35):
E1= __________eV;
E2=___________eV;
E3=_____________eV.
b) based on extension of the formulas you developed in Activities 1 and 2 for the energy levels of the He+ and Li2+
ions, what is the formula for the energy levels of Be3+ ion? (page 35)
c) Complete the following table for the spectrum of Be3+ ion (page 36):
Wavelength, λ (nm)
nfinal
ninitial
6.078
30.388
547.391
Activity 4: Generalization
Based on your above results, write a general formula for the energy levels of an atom with atomic number Z that has
only one electron:
En, atom = ___________________eV
Copyright © 2006 Peter Garik ([email protected]). All rights reserved.