Chapter 9 crossword Landen Vance

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Across
  1. 4. much larger and heavier than electrons they also have a positive charge
  2. 6. two atoms with different numbers of neutrons are called
  3. 7. large and heavy and have no electrical charge
  4. 8. average mass of the naturally occurring isotopes of an element
  5. 9. equal to the number of protons plus neutrons
  6. 10. tiny and light particles that have a negative electrical charge
Down
  1. 1. they are often used for things that are too small or too large to be observed
  2. 2. any of the possible energies an electron may have in an atom
  3. 3. what is the number of protons
  4. 5. also called the wave model