Curated OER
Nuclear Arithmetic
In "Nuclear Arthmetic," first-time physical scientists examine atomic structure and the periodic table of elements. The are given the formula, "N = A-Z," in which N is the number of neutrons, A is the atomic mass, and Z is the atomic...
Kenan Fellows
Isotopic Pennies
Many people confuse atomic mass and atomic numbers. The sixth of seven lessons in a unit requires scholars to find the weight of different groups of pennies. Then, they must solve how many of each type of penny exists in a closed system...
Curated OER
The Average Atom - Isotopes
Seventh graders, in groups, complete an Isotopes model and notice that atomic masses are decimal numbers. These masses are an average of all the isotopes of that element.