Hydrogen Atomic Spectroscopy Experiment

Experiment 34 Hydrogen Atomic Spectra

【Purpose requirement】

1. Determining the wavelength of the emission spectrum of the hydrogen atom Balmer system and the Rydberg constant of hydrogen;

2. Understand the relationship between the hydrogen atom energy level and the spectrum, and draw a hydrogen atom energy level diagram;

3. Understand the light splitting effect of the grating.

【Experimental Principle】

1. Light source and spectrum

There are many kinds of emission spectra of substances. Different substances and light sources with different light emission mechanisms have different spectra. The emission spectra of thermal radiation sources such as incandescent lamps are continuous spectra; atomic gases (or metal vapors) such as hydrogen lamps, mercury lamps, and sodium lamps discharge The spectrum emitted at the time is a discrete line spectrum; the emission spectra of molecular gases, liquids and solids are mostly band spectra.

2. The spectroscopic principle of the grating

Gratings and prisms are commonly used beam splitting elements.

3. Hydrogen atom spectrum

【Experiment content】

1. Instrument adjustment;

2. Determine the grating constant;

3. Observe the hydrogen atom spectrum;

4. Observe the weaker k = ± 1 (purple) spectral line (depending on the quality of the hydrogen lamp) in the Baltic system;

5. Substitute the average value of the diffraction angle and the grating constant into the grating equation to calculate the wavelength of the spectral line in the Balmer system.

【Instruments】

Serial number

equipment name

Model / Specification

Unit price (yuan)

Remarks

1

Spectrometer

JJY-1 / 0-360 °, 1 ′

2980

Compatible with other experiments

2

Hydrogen lamp

With regulated power supply

1500

3

Mercury lamp

GP20Hg / 20W, lifting

580

4

Flat lens grating

1/100

200

5

Plane mirror

Φ36 × 4, dielectric coating

100

6

magnifier

100