1. matter - anything that has volume and mass
2. volume - the amount of space taken up by an object
3. mass - the amount of matter that something is made of
4. gravity - a force of attraction between objects due to their masses
5. weight - a measure of gravitational force exerted on an object
6. newton - (N) unit of measurement of force
7. inertia - the tendency of all objects to resist any change in motion
8. physical change - a change that affects one or more physical properties of a substance
9. chemical change - occurs when one or more substances are changed into entirely new substances with different properties
10. density - the amount of matter in a given space
11. states of matter - the physical forms in which a substance can exist
12. solid - the state in which matter has a definite shape and volume
13. liquid - the state in which matter takes the shape of its container and has a definite volume
14. gas - the state in which matter changes in both shape and volume
15. pressure - the amount of force exerted on a given area
16. Boyle's Law - states that for a fixed amount of gas at a constant temperature, the volume of a gas increases as its pressure decreases
17. Charles's Law - states that for a fixed amount of gas at a constant pressure, the volume of the gas increases as its temperature increases
18. plasma - the state of matter that does not have a definite shape or volume and whose particles have broken apart
19. model - a representation of an object or system
20. atom - the smallest particle into which an element can be divided and still be the same substance
21. nucleus - the tiny, dense, positively charged region in the center of an atom made up of protons and neutrons
22. electron - a negatively charged particle found in all atoms
23. electron cloud - the region inside an atom where electrons are likely to be found
24. protons - the positively charged particles of the nucleus (#of protons = atomic number)
25. neutrons - the particles of the nucleus that have no charge
26. atomic mass - the number of protons in the nucleus of an atom
27. mass number - the sum of the protons and neutrons in an atom
28. isotopes - atoms that have the same number of protons but have different numbers of neutrons