This lab enables students to access some of the terrific physics and chemistry demos provided by the PhET Interactive Simulations Internet site of the University of Colorado at Boulder (https://phet.colorado.edu/
). The demos selected for this lab allow students to trace the development of atomic theory from the late 1800s into the mid 20th century. In particular, three PhET demos are utilized:
Build an Atom
Models of the Hydrogen Atom
The Photoelectric Effect
With Build an Atom, the students assemble models of the first ten elements in chemistry. The model provides concrete examples of the discoveries of JJ Chadwick, Ernst Rutherford, James Chadwick, and Niels Bohr.
With Models of the Hydrogen Atom, the students will be able to trace the evolution of the following atomic models: Thompson's Raisin (Plum) Pudding Model, Rutherford's Solar System Model, Bohr's Quantum Model, Schrodinger's Wave Model, and Heisenberg's Probability Model. The PhET simulation provides demos of each model, which presents their characteristics and allows comparison with other models. The students will also ascertain how each model is able to deal with the problem of atomic spectra.
In The Photoelectric Effect, the students will analyze a well-known experiment wherein light is able to strip electrons from metal. Albert Einstein explained the photoelectric effect in his Nobel Prize winning 1905 paper which invoked Max Planck's quantized interpretation of nature, and also proposed the existence of light particles later named photons. The students can use the demo to corroborate Einstein's observations of the photoelectric effect.
The lab packet provides a detailed introduction and diagrams of each atomic model, and it also explains the history and individual scientific discoveries that led to each iteration of atomic theory. After using a computer to access the PhET demos, the students will use the demos to collect data and answer lab questions concerning each atomic model.
A link is included in the PDF to enable a download of the original MS Word file.