Across
- 1. the lightest alkali metal
- 3. An electrically neutral subatomic particle in the nucleus of an atom
- 6. This family on the periodic table consists of Fluorine and 4 other elements
- 7. a chart that lists all of the elements in order of atomic number
- 9. last name of the designer of the periodic table
Down
- 2. Two atoms with different numbers of neutrons are called ______
- 4. represents the number of protons
- 5. negatively charged particles in an atom
- 8. the number of protons doesn't change in a ____
- 9. Hydrogen is a non _____ on the periodic table