Across
- 4. a negative charge
- 5. the basic unit of elements
- 6. a change that can not be undone and gives off light, gas, heat,change of color, or forming of a precipitate
- 7. no charge
- 9. a substance formed during a reaction
Down
- 1. a change that can undone
- 2. consisting of different or diverse parts
- 3. consisting of the same parts
- 4. central core of the atom
- 8. a positive charge