Across
- 2. unit of a chemical element
- 5. group of atoms bonded together
- 7. of compactness of a substance
- 9. freely but of a constant volume
- 10. substance of The Periodic Table of Elements
- 11. with a neutral charge
- 12. freely to fill any space available
Down
- 1. thing that is composed of two or more seperate elements
- 3. and stable in shape
- 4. with a positive charge
- 6. chemical element with the atomic number 6
- 8. with a negative charge