Atomic Physics Topic

Spectra

Concept 6 demos

Hands holding fiber optic cable and a green laser pointer aimed at the cable tip, with laptop displaying OceanView software showing a sharp spectral peak; small blue USB spectrometer visible at left

Spectrometer

Uses a fiber-optic USB spectrometer to display real-time emission spectra of LED and UV light sources. Students see how different sources produce distinct spectral signatures and can measure wavelengths directly.

$Light tower (right) with three vertically-mounted white light sources and their diffraction grating spectra (left): LED strip spectrum with horizontal line structure from strip segments (top), incandescent smooth continuous rainbow (middle), CFL discrete emission lines (bottom)$

Three White Lights

Compares the spectra of three "white" light sources through diffraction gratings. Students see that incandescent light produces a continuous blackbody spectrum, the CFL shows discrete mercury emission lines, and the …

$Spectroscopy cart in a darkened room with all discharge tubes lit vertically, and their diffracted spectra visible to the right — discrete line spectra and continuous spectra from different sources$

Spectroscopy Cart

Students view discrete emission line spectra from multiple gas discharge tubes using handheld diffraction gratings. Provides direct visual evidence for quantized energy levels and element-specific spectral fingerprints.

Absorption

Concept 2 demos

Glass oil lamp with lit flame on a small platform; two shadows visible on the wall behind -- one orange-yellow from the sodium lamp and one blue-gray from the mercury lamp. A hand holding a spatula is visible near the flame.

Opaque Sodium Flame

Demonstrates that sodium vapor absorbs the same wavelengths it emits (the D-doublet at 589.0 and 589.6 nm). A salt-laden candle flame becomes opaque to sodium lamp light while remaining transparent …

$Composite image: top-left shows bright yellow sodium lamp, top-right shows yellow spectral line through diffraction grating, bottom-left shows faint purple glow of sodium lamp viewed through didymium glass, bottom-right shows the spectral line nearly eliminated$

Didymium Absorption Spectrum

Didymium glass absorbs the yellow sodium D-lines, dramatically dimming a sodium lamp from bright yellow to a faint purple glow. With white light, the glass removes green and yellow bands …

Resonance Radiation

Concept 4 demos

Hourglass-shaped glass flask with mercury pooled in the lower bulb, enclosed in a clear acrylic cylinder with square top and bottom plates

Mercury Triboluminescence

Mercury in a partially evacuated hourglass flask produces a characteristic orange glow when inverted, demonstrating triboluminescence and mercury resonance radiation. Students see mechanical energy converted directly to atomic emission at …

Collection of about 30 mineral samples under long-wave UV light, fluorescing in blue, green, orange, purple, pink, and yellow against a black background

Fluorescent Minerals

Demonstrates fluorescence and atomic energy level transitions using mineral collections under short-wave and long-wave UV light. Students observe wavelength-dependent excitation and Stokes-shifted emission, and several samples also show phosphorescence from …

Collection of UV-sensitive objects under normal room lighting: test tubes with colored fluorescent solutions, laundry detergent powder, phosphorescent toys, and other items on a green table

Fluorescence and Phosphorescence

Distinguishes fluorescence from phosphorescence using a collection of UV-sensitive objects. All glow under UV light, but only the phosphorescent ones continue glowing when the UV is turned off — directly …

Fine Splitting

Concept 1 demo

Zeeman Effect

Spectral lines split in the presence of an external magnetic field due to the lifting of degeneracy. Students observe direct evidence for angular momentum quantization and the magnetic properties of …

Electron Properties

Concept 1 demo

Hand holding rectangular orange perforated board with four yellow-green strings attached to corners, extending to black magnetic anchors on dark surface

Dirac String Trick

Demonstrates that spin-1/2 particles require a 720° rotation (not 360°) to return to their original state. A board connected by strings to fixed points becomes tangled after one full rotation …

Atomic Models

Concept 1 demo

Hydrogen Orbital Models

Student-made physical models illustrate the three-dimensional shapes and probability distributions of hydrogen electron orbitals (s, p, and d). Helps students visualize orbital geometry, nodal surfaces, and the probabilistic nature of …