Across
- 1. A chemical bond in which two atoms share one or more pairs of valence electrons
- 3. A possible, testable explanation for an observation
- 5. A homogenous mixture made by dissolving one substance in another
- 6. A well supported explanation of a range of phenomena
- 8. The sum of the protons and neutrons in the nucleus of an atom
- 9. The force of attraction between molecules of the same substance so that they tend to stay together
- 11. A physical quantity that contains both magnitude and directional information
- 12. A chemical reaction in which a substance reacts rapidly with oxygen
- 14. The substance in a solution that does the dissolving
- 15. The time rate of change of an object's velocity
- 17. Movement in gases and liquids that spreads out particles
- 19. Electrons that are in the highest energy level of an atom
- 21. The tendency of an object to resist changes in its velocity
Down
- 2. The number of protons in an atom
- 4. The distance an object travels plus the direction from the starting point
- 5. A well supported description of a natural phenomenon
- 7. Atoms of an element with the same number of protons but different number of neutrons
- 10. The substance in a solution that gets dissolved
- 13. A force that results when surfaces of objects rub against each other and opposes motion
- 16. An atom or a group of atoms that has a positive or negative charge
- 18. A push or pull that acts on an object
- 20. Found by calculating the distance travelled divided by time