Across
- 4. It is a symbol of wealth
- 5. It prevents goitre
- 6. The most abundant gas on earth
- 7. It is used in fertilisers
- 9. It purifies water
Down
- 1. We need it to breathe
- 2. It is highly reactive
- 3. It is used in galvanisation
- 8. It is used in making computer chips