Across
- 2. Building block of life
- 5. Highly reactive halogen
- 7. Gas used in neon signs
- 9. the lightest element
- 10. Noble gas found in balloons
Down
- 1. Key component of pencil lead
- 3. Element with symbol "Be"
- 4. Element with atomic number 7
- 6. Metal found in batteries
- 8. Gas that supports life