Try 3 free problems on particle counts, isotopes, ions, and atomic notation. Want more reps? Premium opens the full 174-problem bank in sets of 3, 9, or 18.
Work these 3 to find out whether particle counts and atomic symbols are becoming automatic — or whether you need more deliberate practice before they are.
#4Average Atomic Mass
Chlorine has two isotopes: Cl-35 (mass = 34.969 amu, abundance = 75.77%) and Cl-37 (mass = 36.966 amu, abundance = 24.23%). Calculate the average atomic mass of chlorine in amu.
#5Rutherford's Experiment
Rutherford's gold foil experiment showed that most alpha particles passed straight through the foil. What did this indicate about atomic structure?
#6Nuclear Symbol + Ion
Element X has the nuclear symbol 5626X and forms a 2+ ion. Which set of values — protons, neutrons, electrons — is correct for the ion?
Prep for the test — not just the homework
The 3 free problems show you where you stand. The full bank is how you close the gaps before the test.
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174 problems across subatomic particles, isotopes, ions, and atomic notation
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High School Chemistry · Unit 03 · Atomic Structure Practice