<p>ATOMIC NUMBERS OF COMMON ELEMENTS</p><p>Element Symbol Atomic Mass Number Number Hydrogen H 1 1 Helium He 2 4 Carbon C 6 12 Nitrogen N 7 14 Oxygen O 8 16 Sodium Na 11 23 Aluminum Al 13 27 Sulfur S 16 32 Chlorine Cl 17 35 Calcium Ca 20 40 Iron Fe 26 56 Copper Cu 29 64 Silver Ag 47 108 Questions:</p><p>1. What is the atomic number of copper 2. How many proton are these in an atom an atom of N, Cl, Cu 3. How many electrons are there in an atom of Ca, O, N, H 4. Which element has no neutrons in its nuclei? 5. Which element has atoms containing 20 electrons and 20 neutrons 6. Which elements has 30 neutrons in its atoms? 7. Which elements have atoms with the same number of neutrons as protons? How can you tell? 8. Silver has a higher density that the other materials listed in the table. How can you explain this observation?</p>