CK-12 Foundation
Ck 12: Chemistry: Calculating Atomic Mass
[Free Registration/Login may be required to access all resource tools.] Covers definition of atomic mass and calculations of atomic mass.
CK-12 Foundation
Ck 12: Chemistry Simulation: Average Atomic Mass
[Free Registration/Login Required] Students explore how percent abundances of different isotopes affect the average atomic mass for that given element. Students form connections between the average atomic mass and a person's body mass....