Vocabulary

6. the amount of space occupied by a 3-d object
7. one or two or more atoms of an element having the same number of protons in their nuclei but a different number of neutrons
8. release energy as heat
10. a substance containing a hydrogen atom and produces hydronium ion when dissolved in water
11. occurred when a light ray changes direction as it passes from one material to another
13. an attractive force between all objects that have mass
15. a chemical bond that forms when atoms share electrons
16. an influence tending to change the motion of an object or produce motion in a stationary object
17. rate of change of velocity with time
20. a substance that can combine with hydrogen ions and produces hydroxide ions when dissolved in water
22. neutral particle that has no charge
23. a covalent compound made up of many small, repeating units linked together in a chain
24. a vector that represents an object's speed and direction
25. negatively charged particle that occupies the space in the atom outside the nucleus
26. a pulling force applied to an object stretch

1. neutral particle located in the nucleus of an atom
2. the return of light, heat or sound after striking a space
3. a tentative explanation that can be tested with a scientific explanation
4. distance between any two crests or trough on a wave
5. the sum of the number of protons and neutrons in an atom
9. an organic compound used by cells to store and release energy
12. neutral particle that forms as a result of electron sharing
14. mass per unit volume of a material
15. the ability of a material to transfer heart or electricity
18. a squeezing force applied to an object that can make an object shrink
19. absorbs energy as heat
21. an atom that is no longer neutral because it has gained or lost electrons