``` Atomic Calculations-Teacher Answer Key 1. Determine the number of protons, neutrons and electrons for the following elements. Example Elements Number of Number of Number of Protons Neutrons Electrons Hydrogen (H) 1 0 1 Lithium (Li) 3 4 3 Boron (B) 5 6 5 Oxygen (0) 8 8 8 2. Which element has a greater number of protons - Potassium (K) or Selenium (Se)? Potassium has 19 protons and Selenium has 34 according to the elements' atomic numbers. 3. Which element has a smaller number of electrons - Copper (Cu) or Silver (Ag)? Copper has 29 electrons, and Silver has 47 electrons, equaling the number of protons in each element. 4. Which element has a greater number of neutrons - Magnesium (Mg) or Tin (Sn)? Magnesium has 12 neutrons and Tin has 69, calculated by subtracting the atomic number from the atomic mass (rounded to a whole number). vvEPA Environmental Protection RadTown Radioactive Atom Activity Set EPA 402-B-19-018 Agency https://www.EPA.gov/RadTown/Activitv-2-Atomic-Math-and-Shorthand ````------- `