Across
- 3. the number of an element on the periodic table (determined by the number of atoms)
- 6. a table that contains all the basic elements
- 8. particle with a positive charge
- 9. particle with a negative charge
Down
- 1. a pure substance consisting of atoms
- 2. centre of an atom
- 4. foundation of elements
- 5. particle with neutral/no charge
- 7. the mass of an atom