The Butterfly Orbital
Publication No. 11983
A centrifuge can be used to provide a physical model of electron orbitals. Students often initially experience difficulty in visualizing abstract concepts like the quantum mechanics of the atom. This demonstration provides students with a simple, visual analogy of electron motion around the nucleus.
Battery, D size
Bracken’s Demonstration Spinner
Butterfly, artificial, with wire*
Candle or burner
Dissection needle or paper clip
Florist’s wire, 18"*
Soda bottle cap*
*Materials included in kit.
This demonstration is considered nonhazardous. Follow all normal classroom safety precautions, wear safety glasses. Do not touch the motor axle while the rotor is spinning. Remove the battery from the Bracken’s Demonstration Spinner when not in use and during storage.
Student Worksheet PDF
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering PracticesDeveloping and using models
Constructing explanations and designing solutions
Disciplinary Core IdeasMS-PS1.A: Structure and Properties of Matter
HS-PS1.A: Structure and Properties of Matter
Crosscutting ConceptsSystems and system models
Stability and change
Answers to Questions
All atoms are composed of a nucleus (containing protons and neutrons) and electrons spinning around the nucleus. A common misconception is that the electrons orbit the nucleus similar to the way that planets orbit the Sun—in neatly placed relatively circular orbits. The actual location of an electron around a nucleus cannot be determined. Objects at the subatomic level do not behave like objects in the macroscopic world. At the subatomic level, the position and the energy of subatomic particles cannot be determined simultaneously. This is known as Heisenberg’s uncertainty principle. If the position of an electron is determined accurately, then the energy of that electron will be very uncertain. Vice versa, if the energy of the electron is accurately measured, then it is nearly impossible to find the exact location of that electron. However, we can determine the probability of finding an electron of a certain energy in a given region of space.The probability distribution of locating an electron in a region of space around a nucleus is known as the electron density cloud. The electron density cloud represents the three-dimensional orbital of the electron around the nucleus. Figure 5 represents the s-orbital of an electron at a low-energy state. It shows that there is a higher probability of locating an electron at a short distance from the nucleus than further away from the nucleus.
Flinn Scientific would like to thank Jeff Bracken, chemistry teacher at Westerville North High School in Westerville, Ohio, for sharing his original idea with us.