Across
- 4. (of a bond)sharing a pair of electrons
- 6. a chemical element found in all living things, existing in a pure state as diamond
- 8. a quality or characteristic that something has
- 9. physical substance that everything in the world is made of
- 10. the part of an atom that contains most of its mass and that carries a positive electric charge
Down
- 1. the process of a liquid changing or being changed into a gas
- 2. a group of atoms that forms the smallest unit that a substance can be divided into without a change in its chemical nature
- 3. an occasion when two or more people or things communicate with or react to each other
- 5. that is very strong and cannot easily be destroyed
- 7. a substance formed by a chemical reaction of two or more elements