The Gold Foil Mystery: How Do We Know the Atom Has a Tiny Core?
Sim Lesson
Students use The Gold Foil Mystery simulation to fire alpha particles at gold foil and observe that almost all pass straight through while a rare few deflect sharply, evidence that positive charge is concentrated in a tiny core. Lesson Purpose Students often picture an atom as a solid ball of charge. The rare wide-angle bounces provide evidence that positive charge is packed into a tiny central region with mostly empty space around it.
You cannot see inside an atom, so how did scientists figure out that its positive charge is packed into a tiny central spot? They fired tiny particles at a thin sheet of gold and watched where they went. In this lesson, you will use The Gold Foil Mystery simulation to fire alpha particles at gold foil and study how they scatter.
Topics and standards: Science, Energy, Chemistry, Elements, Physics, Physical Science, Nuclear Energy, Simulation, Electricity & Magnetism, HS-PS3-5, Grades 9-12, HS-PS2-4, Matter & Its Interactions, AP Sciences, SC.912.P.8.3, TEKS Science CHEM.6.A, CHEM1-PS1-1, 3.2.9-12.L, 3.2.9-12.S