7.5 CW 1

3. an element that is a poor conductor of heat and electricity
4. the principle that mass is not created or destroyed in a closed system
6. the force that holds atoms together in a molecule or compound
7. a vertical column on the periodic table where elements have similar properties
8. a mixture in which one substance is evenly dissolved in another
10. a horizontal row on the periodic table
11. a subatomic particle with a negative charge that moves around the nucleus
15. a substance made of two or more different elements chemically combined
18. two or more atoms chemically bonded together
19. the smallest unit of matter that makes up an element
20. particles smaller than an atom such as protons, neutrons, and electrons
22. the branch of science that studies matter and how it changes

1. a system in which matter can enter or leave
2. characteristics of matter that can be observed without changing the substance
3. a subatomic particle with no charge found in the nucleus
5. a combination of two or more substances that are not chemically bonded
9. a chart that organizes all known elements by their properties
12. a pure substance made of only one type of atom
13. the center of an atom where protons and neutrons are located
14. the amount of space an object or substance occupies
16. a system in which matter cannot enter or leave
17. the amount of mass in a given volume
21. a subatomic particle with a positive charge found in the nucleus