Refer to Model 1. Boron exists in two isotopes, boron-10 and boron-11. Name: Isotope Practice Worksheet. # of protons Rocket Calculations - multiplayer math game - Fight in 1vs1 math duel with other users - Every correct answer will accelerate your ship, every wrong answer will slow it down. sweet things to write in a baby book. View Homework Help - Isotope-Practice-Worksheet-KEY.doc from MATH 101 at Franklin County High School. Use the, Q: