Elements
Across
- 2. number of protons in an atom
- 7. a column in the periodic table
- 9. the organized array of all the chemical elements in order of increasing atomic number
- 10. the horizontal rows of the periodic table
- 11. each of more than one hundred substances that cannot be chemically interconverted
Down
- 1. made up or consisting of two or more existing parts or elements
- 3. neutral electric charge
- 4. basic unit of a chemical unit
- 5. positive electric charge
- 6. negative electric charge
- 8. a group of atoms bonded together