How to Use This Presentation

1. How to Use This Presentation • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. • You may exit the slide show at any time by pressing the Esc key.

2. Resources Chapter Presentation Visual Concepts Transparencies Standardized Test Prep

3. Chapter 2 Chemistry of Life Table of Contents Section 1 Composition of Matter Section 2 Energy Section 3 Water and Solutions

4. Section 1 Composition of Matter Chapter 2 Objectives • Definethe term matter. • Explainthe relationship between elements and atoms. • Draw and label a model of the structure of an atom. • Explain howcompounds affect an atom’s stability. • Contrast covalent and ionic bonds.

5. Section 1 Composition of Matter Chapter 2 Matter • Matteris anything that occupies space and has mass. • Massis the quantity of matter an object has.

6. Section 1 Composition of Matter Chapter 2 Matter

7. Section 1 Composition of Matter Chapter 2 Elements and Atoms • Elementsare made of a single kind of atom and cannot be broken down by chemical means into simpler substances. • Atoms are composed of protons, neutrons, and electrons.

8. Section 1 Composition of Matter Chapter 2 Element

9. Section 1 Composition of Matter Chapter 2 Elements and Atoms, continued • The Nucleus • Protons and neutrons make up the nucleus of the atom.

10. Section 1 Composition of Matter Chapter 2 Elements and Atoms, continued • Electrons • Electronsmove about the nucleus in orbitals. • An orbital is a three-dimensional region around a nucleus that indicates the probable location of an electron.

11. Section 1 Composition of Matter Chapter 2 Elements and Atoms, continued • Isotopes • Atoms of the same element that have a different number of neutrons are calledisotopes.

12. Section 1 Composition of Matter Chapter 2 Compounds • Compoundsconsist of atoms of two or more elements that are joined by chemical bonds in a fixed proportion.

13. Section 1 Composition of Matter Chapter 2 Compounds

14. Section 1 Composition of Matter Chapter 2 Compounds, continued • Covalent Bonds • A covalent bond is formed when two atoms share electrons.

15. Section 1 Composition of Matter Chapter 2 Covalent Bonding

16. Section 1 Composition of Matter Chapter 2 Compounds, continued • Ionic Bonds • An ionic bond is formed when one atom gives up an electron to another. The positive ion is then attracted to a negative ion to form the ionic bond.

17. Section 1 Composition of Matter Chapter 2 Ionic Bonding

18. Section 1 Composition of Matter Chapter 2 Ionic Bonding

19. Section 2 Energy Chapter 2 Objectives • Describethe physical properties of each state of matter. • Describethe role of reactants and products in chemical reactions. • Explainthe relationship between enzymes and activation energy. • Explainhow oxidation and reduction reactions are linked.

20. Section 2 Energy Chapter 2 Energy and Matter • States of Matter • Addition of energy to a substance can cause its state to change from a solid to a liquid and from a liquid to a gas.

21. Section 2 Energy Chapter 2 Energy

22. Section 2 Energy Chapter 2 Energy and Chemical Reactions • Reactantsare substances that enter chemical reactions. • Products are substances produced by chemical reactions.

23. Section 2 Energy Chapter 2 Energy and Chemical Reactions

24. Section 2 Energy Chapter 2 Energy and Chemical Reactions, continued • Activation Energy • Enzymes lower the amount of activation energy necessary for a reaction to begin in living systems.

25. Section 2 Energy Chapter 2 Activation Energy and Chemical Reactions

26. Section 2 Energy Chapter 2 Energy and Chemical Reactions, continued • Oxidation Reduction Reactions • A chemical reaction in which electrons are exchanged between atoms is called an oxidation-reduction reaction.

27. Section 3 Water and Solutions Chapter 2 Objectives • Describethe structure of a water molecule. • Explainhow water’s polar nature affects its ability to dissolve substances. • Outline the relationship between hydrogen bonding and the different properties of water. • Identify the roles of solutes and solvents in solutions. • Differentiate between acids and bases.

28. Section 3 Water and Solutions Chapter 2 Polarity • Water is considered to be apolarmolecule due to anuneven distribution of charge. • The electrons in a water molecule are shared unevenly between hydrogen and oxygen.

29. Section 3 Water and Solutions Chapter 2 Polarity, continued • Solubility of Water • The polarity of water makes it effective at dissolving other polar substances such as sugars, ionic compounds, and some proteins.

30. Section 3 Water and Solutions Chapter 2 Hydrogen Bonding • A hydrogen bondis the force of attraction between a hydrogen molecule with a partial positive charge and another atom or molecule with a partial or full negative charge.

31. Section 3 Water and Solutions Chapter 2 Hydrogen Bonding, continued • Cohesion and Adhesion • Cohesion is an attractive force that holds molecules of a single substance together, such as water molecules. • Adhesionis the attractive force between two particles of different substances, such as water molecules and glass molecules.

32. Section 3 Water and Solutions Chapter 2 Comparing Cohesion and Adhesion

33. Section 3 Water and Solutions Chapter 2 Hydrogen Bonding, continued • Temperature Moderation • Water has the ability to absorb a relatively large amount of energy as heat and the ability to cool surfaces through evaporation.

34. Section 3 Water and Solutions Chapter 2 Hydrogen Bonding, continued • Density of Ice • Solid water is less dense than liquid water due to the shape of the water molecule and hydrogen bonding.

35. Section 3 Water and Solutions Chapter 2 Solutions • A solutionconsistsof a solute dissolved in a solvent.

36. Section 3 Water and Solutions Chapter 2 Acids and Bases • Ionization of Water • Water ionizes intohydronium ions(H3O+) and hydroxide ions (OH–).

37. Section 3 Water and Solutions Chapter 2 Acids and Bases, continued • Acids • Acidic solutionscontain more hydronium ions than hydroxide ions.

38. Section 3 Water and Solutions Chapter 2 Acids and Bases, continued • Bases • Basic solutionscontain more hydroxide ions than hydronium ions.

39. Section 3 Water and Solutions Chapter 2 Bases

40. Section 3 Water and Solutions Chapter 2 Acids and Bases, continued • pH • Scientists have developed a scale for comparing the relative concentrations of hydronium ions and hydroxide ions in a solution. This scale is called the pH scale, and it ranges from 0 to 14.

41. Section 3 Water and Solutions Chapter 2 The pH Scale

42. Section 3 Water and Solutions Chapter 2 Acids and Bases, continued • Buffers • Buffersare chemicals that neutralize the effects of adding small amounts of either an acid or a base to a solution.

43. Section 3 Water and Solutions Chapter 2 pH

44. Chapter 2 Standardized Test Prep Multiple Choice 1. The way in which elements bond to form compounds depends on which of the following? A. the model of the atom B. the structural formula of the compound C. the dissociation of the ions in the compound D. the number and arrangement of electrons in the atoms of the elements

45. Chapter 2 Standardized Test Prep Multiple Choice, continued 1. The way in which elements bond to form compounds depends on which of the following? A. the model of the atom B. the structural formula of the compound C. the dissociation of the ions in the compound D. the number and arrangement of electrons in the atoms of the elements

46. Chapter 2 Standardized Test Prep Multiple Choice, continued 2. If an atom is made up of 6 protons, 7 neutrons, and 6 electrons, what is its atomic number? F. 6 G. 7 H. 13 J. 19

47. Chapter 2 Standardized Test Prep Multiple Choice, continued 2. If an atom is made up of 6 protons, 7 neutrons, and 6 electrons, what is its atomic number? F. 6 G. 7 H. 13 J. 19

48. Chapter 2 Standardized Test Prep Multiple Choice, continued The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. 3. The amount of energy needed for this chemical reaction to begin is shown by the line rising from the reactants. What is this energy called? A. chemical energy B. electrical energy C. activation energy D. mechanical energy

49. Chapter 2 Standardized Test Prep Multiple Choice, continued The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. 3. The amount of energy needed for this chemical reaction to begin is shown by the line rising from the reactants. What is this energy called? A. chemical energy B. electrical energy C. activation energy D. mechanical energy

50. Chapter 2 Standardized Test Prep Multiple Choice, continued The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. 4. Suppose that this reaction needs a catalyst to proceed. In the absence of a catalyst, the activation energy would be which of the following? F. larger than what is shown G. the same as what is shown H. smaller than what is shown J. not much different from what is shown