2. ©2015 Science Island Matter is anything that has mass and takes up space. 1 1

3. ©2015 Science Island Elements are pure substances that consist entirely of one type of atom. 2 2

4. ©2015 Science Island List the four most abundant elements in living things. oxygen carbon hydrogen nitrogen 3 3

5. ©2015 Science Island A compound is formed when two or more elements chemically combine in a fixed ratio. 4 4

6. ©2015 Science Island How many atoms of each element are in one molecule of the compound carbon dioxide? 1 atom of carbon & 2 atoms of oxygen 5 5

7. ©2015 Science Island The smallest piece or particle of an element is an atom. 6 6

8. ©2015 Science Island List the 3 subatomic particles. protons neutrons electrons 7 7

9. ©2015 Science Island Match the subatomic particles with their charge and location: c 1) electrons a. no charge, nucleus a 2) neutrons b. positive, nucleus b 3) protons c. negative, outside nucleus 8 8

10. ©2015 Science Island What is the atomic number of an element? The number of protons in the nucleus. (Ex:The atomic number of oxygen is 8.) 9 9

11. ©2015 Science Island Carbon usually has 6 protons and 6 neutrons and is called carbon 12. Carbon 13 has an additional neutron and is an isotope of carbon. 10

12. ©2015 Science Island What type of element is used to produce medical images such as these? radioactive isotopes 11

13. ©2015 Science Island The outer, or valence, electrons are involved in forming bonds. 12

14. ©2015 Science Island When electrons are transferred from one atom to another an ionic bond is formed. 13 Science Island

15. ©2015 Science Island If an atom loses an electron, it becomes a positive ion. 14

16. ©2015 Science Island What type of bonds are shown below? Covalent – electron pairs are being shared 15

17. ©2015 Science Island How many covalent bonds can an atom of carbon form? 4 16

18. ©2015 Science Island Slight attractions between molecules that develop between oppositely charged regions of nearby molecules are called van der Waals forces. 17

19. ©2015 Science Island A polar molecule is one in which the charges are unevenly distributed. 18

20. ©2015 Science Island List the reactants and products in this chemical reaction. 19 Science Island reactants products

21. ©2015 Science Island Draw a water molecule and label the negatively charged end and the positively charged end. 20 - +

22. ©2015 Science Island What type of bond is shown between the water molecules? 21 hydrogen bonds

23. ©2015 Science Island Complete the 4 unique properties of water: Cohesion and adhesion High specific heat capacity Lower density of ice Water’s ability to dissolve other substances (universal solvent) 22

24. ©2015 Science Island The attraction between water molecules is an example of cohesion. 23

25. ©2015 Science Island The attraction between water molecules and the sides of a container is an example of adhesion. 24

26. ©2015 Science Island Cohesion between water molecules forms an invisible boundary called surface tension. 25

27. ©2015 Science Island What property of water causes the temperature in coastal areas to be more stable? high specific heat capacity 26 Science Island

28. ©2015 Science Island What property of water makes it possible for fish and other aquatic organisms to survive freezing conditions ? low density of ice 27 Emily Stone / National Science Foundation

29. ©2015 Science Island A uniform mixture of two or more substances is a solution. 28

30. ©2015 Science Island In this photo, what substance is the solvent? water (in the coffee) The solute? sugar 29

31. ©2015 Science Island An aqueous solution in one in which water is the solvent. 30

32. ©2015 Science Island Name the two ions that form when water molecules break apart in a solution. H + hydrogen ions OH - hydroxide ions 31

33. ©2015 Science Island Label the pH scale below: 32 strong acid strong base weak base weak acid neutral Science Island

34. ©2015 Science Island What has been mixed with the water in the first beaker? 33 base

35. ©2015 Science Island What ions will form in the second beaker? 34

36. ©2015 Science Island The bicarbonate ion, HCO 3 - can accept H + ions or donate them to a solution. This helps regulate pH levels, therefore HCO 3 - is a buffer. H 2 CO 3 HCO 3 - + H + 35

37. ©2015 Science Island