STUDY OF HYDROGEN ATOM SPECTRUM RYDBERG’S CONSTANT DETERMINATION
The purpose of the work:
- to determine wavelengths of hydrogen atom visible spectrum;
- to calculate Rydberg’s constant;
- to determine energy and mechanical characteristics of hydrogen atom
Devices and accessories:
1. spectroscope;
2. discharge tube;
3. current source
Task 1. Monochromator calibration graph drawing
1.1. Obtain readings of monochromator drum for all wavelength of krypton atom. Enter the results into table 1.
Table 1
Spectrum line color
Theoretical values of wavelengths
Drum reading
λ, Å
λ, m
Bright red
Orange
Yellow-orange
Yellow
Green
Blue
Blue
Violet
Violet
Violet
Draw calibration graph using plotting paper.
Task 2. Determination of wavelengths of hydrogen atom visible spectrum lines
2.1. Determine positions of red, blue, dark blue and violet lines of hydrogen atom using drum scale.
2.2. Determine wavelengths of hydrogen atom visible spectrum lines Íα, Íβ, Íγ, Íδ using monochromator calibration graph. Enter the results into table 2
Table 2
Color of Spectrum line
Line symbol
Drum reading
Spectrum line wavelength determined by graphical method, λ, m
Rydberg’s constant, R¥, m–1
Average value of Rydberg’s constant, R¥ave, m–1
Absolute error, DR¥ ,m–1
Fractional error, e, %
Red
Ha
Blue
Hb
Dark blue
Hg
Violet
Hd
Task 3. Rydberg’s constant determination
3.1. Calculate Rydberg’s constant according to the formula: