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1. Section 2 Section 2 Section 1 Section 1 Section 1 & 2 1pt 1 pt 1 pt 1pt 1 pt 2 pt 2 pt 2pt 2pt 2 pt 3 pt 3 pt 3 pt 3 pt 3 pt 4 pt 4 pt 4pt 4 pt 4pt 5pt 5 pt 5 pt 5 pt 5 pt

2. The minimum amount of energy that has to be added to start a reaction is the Exothermic energy Endothermic energy Activation energy Chemical energy

3. c. Activation energy

4. Which of the following does NOT increase the number of particles of a substance available to react in a chemical reaction? Increasing the concentration Increasing the surface area Adding a catalyst Increasing the mass

5. C. Adding a catalyst

6. A material used to decrease the rate of a chemical reaction is a(n) inhibitor catalyst enzyme fuel

7. A. inhibitor

8. Which of the following is an example of how to supply activation energy to begin a reaction? Cool the reaction flask in an ice bath Add a catalyst Heat the reaction flask on a hot plate Add an inhibitor

9. C. Heat the reaction flask on a hot plate

10. Chemicals that act as biological catalysts by speeding up reactions in living things are Inhibitors Enzymes Fuels Reactants

11. B. Enzymes

12. Explain the following in terms of factors that affect the rate of a chemical reaction. A) Chemical reactions in living things would not be possible without the enzymes found in cells.

13. Enzymes are catalysts. They speed up chemical reactions by lowering the activation energy of reactions needed for life. Without the presence of enzymes in cells, the reactions in living things would occur too slowly or require temperatures that are too high for cells to survive.

14. Explain the following in terms of factors that affect the rate of a chemical reaction. B) Wood burns at a steady rate, but sawdust may explode if a spark ignites it. (Sawdust is tiny particles of wood made from sawing wood.).

15. Sawdust has a greater surface area than wood. Increased surface area of a reactant will increase the rate of a chemical reaction. In this case, more of the reactant (sawdust) will come in contact with oxygen, so a spark is enough to start an explosion.

16. The minimum amount of energy that has to be added to start a reaction is the Exothermic Edothermic energy Activation energy Chemical energy

17. C. Activation energy

18. Table sugar and table salt are examples of Atoms Elements Mixtures Pure substances

19. d. Pure substances

20. Substances that CANNOT be broken down chemically into other substances Elements Compounds Mixtures Solutions

21. Elements

22. All elements are composed of extremely small particles called Compounds Mixtures Atoms Molecules

23. C. Atoms

24. Which of these statements is false? Oxygen and copper are examples of elements. Elements are pure substances. Atoms of different elements can combine to form compounds. Atoms of different elements are the same.

25. D. Atoms of different elements are the same.

26. What holds atoms together in a molecule? Density Gravity Physical bonds Chemical bonds

27. D. Chemical bonds

28. Anything that has mass and takes up space is called Matter Energy Heterogeneous Homogeneous

29. A. Matter

30. Lemonade consists of several substances that are NOT chemically combined, so lemonade is classified as a(n) Element Compound Mixture Pure substance

31. C. Mixture

32. If you heat a liquid and measure the temperature at which it boils, you are measuring a(n) Atomic property Physical property Chemical property Molecular property

33. Physical property

34. If you describe methane as a gas that easily catches fire, you are describing a State of matter Physical property Chemical property Chemical formula

35. C. Chemical property

36. H2O, CO2, and C12H22O11 are all examples of chemical Properties Changes Bonds Formulas

37. D. Formulas

38. Soil, a salad, and sugar water are all examples of Elements Compounds Mixtures Atoms

39. C. Mixtures

40. Explain the difference between a mixture and a compound

41. A mixture consists of two or more substances that are mixed together but are not chemically combined. The individual substances in a mixture keep their separate properties. A compound is a substance formed when two or more elements combine chemically. The properties of a compound are very different from those of the elements that formed it.

42. Explain how you could find out whether or not an unknown liquid was water.

43. You could investigate some of the characteristic properties of the unknown substance. If the unknown substance is water, it will have the same freezing point, the same boiling point, the same density, and the same chemical reactivity as water.

44. Explain the difference between atoms and molecules.

45. Atoms are the smallest particles of an element. Atoms can combine with other atoms to form molecules. A molecule is a group of atoms that are joined together and act as a single unit. Molecules can be made of different kinds of atoms or the same kind of atoms. Atoms within a molecule are held together by chemical bonds.

46. Circle the letter of each mixture below that is heterogeneous Damp soil Sugar water Brass Salad

47. A and D damp soil and salad

48. Study guide is your workbook pages 23-25 for CHAPTER 2.1

49. Study guide is your workbook pages 23-25 for CHAPTER 2.1

50. Study guide is your workbook pages 91 -94 for Chapter 6.3