chemistry

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Across
  1. 2. positive part of atom
  2. 4. groups of atoms held together by chemical bonds
  3. 6. negative part of atom
  4. 7. protons neutrons and electrons make
  5. 8. outer most shell of electrons
  6. 9. transferred electrons is a ____ bond
Down
  1. 1. shared electrons are a ____ bond
  2. 3. neutral part of atom
  3. 5. numbers and letters to make a
  4. 6. reaction that gives off heat