Across
- 3. vertical columns of the periodic table
- 5. bases that dissolve in water
- 7. Who was the first person to come up with the idea of the atom?
- 8. horizontal rows on the periodic table
- 9. substances containing only one kind of atom
- 10. a term that describes atoms that have the outermost shell filled and are less likely to form compounds
- 11. theory the ideas that scientists have about atoms based on repeated observations of how atoms act in experiments
- 12. a type of molecule when 2 or more elements are chemically combined
- 15. mass the approximate sum of the number of protons and neutrons
- 17. the study of matter, what it is made of, what its usual characteristics are, and how it reacts with other matter
Down
- 1. a machine designed to smash atoms
- 2. solutions with a pH of 7.0; they are neither basic nor acidic
- 4. Who developed the “chocolate chip” model of the atom?
- 6. the smallest piece of an element that can be recognized as that element
- 12. symbols abbreviations for the names of the elements
- 13. units that are formed when atoms join with other atoms
- 14. an atom that has gained or lost an electron
- 15. refers to the number of protons in an atom’s nucleus
- 16. J.J. Thomson discovered which atomic particle?