Science Test 6

12345678910111213141516171819202122232425262728
Across
  1. 2. whenever a substance reacts rapidly with oxygen
  2. 3. opposite charges
  3. 6. tiny group of two or more atoms that are bonded tightly together
  4. 8. hold a positive charge
  5. 10. hold a negative charge
  6. 13. tiny particles of which all matter is composed
  7. 15. substance composed of more than one type of atom bonded together
  8. 18. 99% of earth's atmosphere
  9. 19. electrons in orbit at the same distance from the nucleus
  10. 22. substances composed of one type of atom
  11. 23. the measure of the pull of gravity on an object
  12. 26. amount of matter that makes up an object
  13. 27. the periodic table is divided into ___ groups: Metals, Metalloids, and Nonmetals
  14. 28. Dmitri Mendeleev created the ____________
Down
  1. 1. scientists who study chemistry
  2. 4. atoms of elements or compounds are rearranged to form substances
  3. 5. most common alkaline earth metal
  4. 7. a basic building block of the complex compounds found in your body
  5. 9. unit used to measure mass
  6. 11. number of protons in an atom
  7. 12. like charges
  8. 14. study of what substances are made of and how one substance can be changed into another
  9. 16. the amount of matter in one unit of volume
  10. 17. dense core of an atom
  11. 20. anythings lacking in electrical charge
  12. 21. hold no charge
  13. 24. anything that takes up space and has mass
  14. 25. only liquid metal