Chemical Education

Orbital Shaped Standing Waves Using Chladni Plates

Abstract

Chemistry students are often introduced to the concept of atomic orbitals with a representation of a one-dimensional standing wave. The classic example is the harmonic frequencies which produce standing waves on a guitar string; a concept which is easily replicated in class with a length of rope. From here, students are typically exposed to a more realistic three-dimensional model, which can often be difficult to visualize. Extrapolation from a two-dimensional model, such as the vibrational modes of a drumhead, can be used to convey the standing wave concept to students more easily. We have opted to use Chladni plates which may be tuned to give a two-dimensional standing wave which serves as a cross-sectional representation of atomic orbitals. The demonstration, intended for first year chemistry students, facilitates the examination of nodal and anti-nodal regions of a Chladni figure which students can then connect to the concept of quantum mechanical parameters and their relationship to atomic orbital shape.

Content

Thumbnail image of MathSI.pdf

Supplementary material

Thumbnail image of Chladni manuscript_20191030.docx
Chladni manuscript 20191030
Thumbnail image of SUPPORTING INFORMATION Materials and Setup Photos.docx
SUPPORTING INFORMATION Materials and Setup Photos
Thumbnail image of Chladni plates 2 - Petite.mov
Chladni plates 2 - Petite