Across
- 1. It is one of the most precious metals.
- 4. It is the only element that its atom can exist without neutrons.
- 5. It is commonly used in electrical wires and cables.
- 7. It is vital for building strong bones and teeth.
- 8. It is a semi-metal which is used to make computer chips.
- 9. This gas can relight a glowing splint.
Down
- 2. It contributes about 78% of the earth's atmosphere.
- 3. This gas is widely used in luminous advertisement signs.
- 6. It glows and burns and is associated with glowing skulls and graveyard ghosts.
- 7. This gas helps keep swimming pools clean.