1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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. How to Use This Presentation

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Transparencies Standardized Test Prep Visual Concepts Resources

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chemistry of Life Chapter 2 Table of Contents Section 1 Composition of Matter Section 2 Energy Section 3 Water and Solutions

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Objectives Define the term matter. Explain the relationship between elements and atoms. Draw and label a model of the structure of an atom. Explain how compounds affect an atom’s stability. Contrast covalent and ionic bonds.

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Matter Matter is anything that occupies space and has mass. Mass is the quantity of matter an object has.

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In recent times, we have begun to study matter at the very high temperatures and pressures which typically occur on the Sun, or during re-entry from space. Under these conditions, the atoms themselves begin to break down; electrons are stripped from their orbit around the nucleus leaving a positively charged ion behind. The resulting mixture of neutral atoms, free electrons, and charged ions is called a plasma, the forth state of matter.

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Elements and Atoms Elements are made of a single kind of atom and cannot be broken down by chemical means into simpler substances. About 100 million atoms side by side = 1 cm About 25 different chemical elements are essential to life 4 elements make up 96% of the human body by weight. Which ones are they?

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Carbon, hydrogen, oxygen, and nitrogen make up the bulk of living matter, but there are other elements necessary for life. Trace elements are essential (<0.01% wet weight). Flouride is in our water and iodine is in our salt. Iron is in our red blood cells and is found in the heme group of the hemoglobin molecule. Table 2.2

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Goiters are caused by iodine deficiency The thyroid gland requires.15mg I/day for normal function. Iodine is essential in the formation of thyroid hormone, which is composed of four molecules of iodine and one molecule of the amino acid tyrosine. Figure 2.2

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Elements and Atoms, continued Atoms of the various elements are made up of protons, neutrons and electrons. The Nucleus –Protons and neutrons make up the nucleus of the atom. –Protons have a positive charge –Neutrons are neutral + _ N

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Elements and Atoms, continued Electrons –Electrons move about the nucleus in orbitals and have a negative charge. –The number of electrons equals the number of protons; thus an atom is neutral. –An orbital is a three- dimensional region around a nucleus that indicates the probable location of an electron.

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The atom is held together by attractions between the positively charged protons and negatively charged electrons Figure 2.4B B. Carbon atom 6 6 6 Protons Neutrons Electrons Nucleus Neutrons are electrically neutral The number of neutrons may vary Variant forms of an element are called isotopes Atoms of each element are distinguished by a specific number of protons. The number of protons is equal to the number of electrons.

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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 called isotopes.

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Table 2.4 – The number of neutrons may vary – Variant forms of an element are called isotopes – Some isotopes are radioactive – The atomic mass of Carbon is 12.01. This is the average mass of the various isotopes of carbon found in nature. C-14 is radioactive. % in nature 98.89 C12 1.11 C13 Trace C14

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Radioactive isotopes can help or harm us Radioactive isotopes can be useful tracers for studying biological processes. Living cells do not know the difference between isotopes. Every organ in our bodies acts differently from a chemical point of view. Doctors and chemists have identified a number of chemicals which are absorbed by specific organs. The thyroid, for example, takes up iodine, the brain consumes quantities of glucose, and so on. With this knowledge, radiopharmacists are able to attach various radioisotopes to biologically active substances. Once a radioactive form of one of these substances enters the body, it is incorporated into the normal biological processes and excreted in the usual ways. http://www.uic.com.au/nip26.htm

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu PET scanners use radioactive isotopes to create anatomical images http://en.wikipedia.org/wiki/Positron_emission_tomography A substance that emits positrons is injected into the patient. The positrons collide with electrons in tissues that are metabolically active. The energy released by these collisions is registered as “hot spots”. Radioactive isotopes can help or harm us Figure 2.5BFigure 2.5A

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Isotopes Used in Medicine Molybdenum-99 Used as the “parent” to produce technetium-99m the most widely used isotope in nuclear medicine. Technetium-99m Most widely used to image the skeleton and heart muscle. Technetium-99m decays by a process called "isomeric"; which emits gamma rays and low energy electrons. Since there is no high energy beta emission the radiation dose to the patient is low. Chromium-51 Used to label rbc’s and gastro intestinal protein loss Cobalt-60 Used for radiotherapy Dysprosium-165 Used in the synovectomy treatment of arthritis Ytterbium-169 Cerebrospinal studies of the brain Iodine-125 Used in prostate and brain cancer therapy. Used to diagnose deep vein thrombosis. Used to assay for hormones present in minute quantities Iodine 131 Treating thyroid cancer and imaging the thyroid. Used in diagnosis of liver function, kidney blood flow and urinary tract obstruction. A strong gamma emitter, but is used for beta therapy.

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Carbon Dating Research Carbon Dating. Discover the theory, the advantages and the drawbacks of the technique. Complete a 2 page essay on the use of Carbon Dating Beta decay is when an electron and positron are emitted

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Electrons are arranged in shells –The outermost shell determines the chemical properties of an atom –In most atoms, a full outer shell holds eight electrons. A happy atom!!!!!! Electron arrangement determines the chemical properties of an atom

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Atoms whose shells are not full tend to interact with other atoms and gain, lose, or share electrons. Hum….. Figure 2.6 HYDROGEN (H) Atomic number = 1 CARBON (C) Atomic number = 6 NITROGEN (N) Atomic number = 7 OXYGEN (O) Atomic number = 8 Electron Outermost electron shell (can hold 8 electrons) First electron shell (can hold 2 electrons)

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Compounds Compounds consist of atoms of two or more elements that are joined by chemical bonds in a fixed proportion.

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Sodium and chloride ions bond to form sodium chloride, common table salt Figure 2.7B Na + Cl –

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu When atoms gain or lose electrons, charged atoms called ions are created –An electrical attraction between ions with opposite charges results in an ionic bond Ionic bonds are attractions between ions of opposite charge Figure 2.7A Na Sodium atom Cl Chlorine atom Na + Sodium ion Cl – Chloride ion Sodium chloride (NaCl) NaClNaCl + –

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 Ionic Bonding Section 1 Composition of Matter

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Compounds, continued Covalent Bonds –A covalent bond is formed when two atoms share electrons.

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Some atoms share outer shell electrons with other atoms, forming covalent bonds –Atoms joined together by covalent bonds form molecules Covalent bonds, the sharing of electrons, join atoms into molecules

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Because of the nature of ionic and covalent bonds, the materials produced by those bonds tend to have quite different macroscopic properties. The atoms of covalent materials are bound tightly to each other in stable molecules, but those molecules are generally not very strongly attracted to other molecules in the material. On the other hand, the atoms (ions) in ionic materials show strong attractions to other ions in their vicinity. This generally leads to low melting points for covalent solids, and high melting points for ionic solids. For example, the molecule carbon tetrachloride is a non-polar covalent molecule, CCl 4. It's melting point is - 23°C. By contrast, the ionic solid NaCl has a melting point of 800°C. Furthermore, ionic bonds themselves tend to be weaker than covalent bonds, but this is a topic for a more advanced chemistry course as it is a generalization. Ionic Compounds 1. Crystalline solids (made of ions) 2. High melting and boiling points 3. Conduct electricity when melted 4. Many soluble in water but not in nonpolar liquids Covalent Compounds 1. Gases, liquids, or solids (made of molecules) 2. Low melting and boiling points 3. Poor electrical conductors in all phases 4. Many soluble in nonpolar liquids and not in water

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy Chapter 2 Objectives Describe the physical properties of each state of matter. Describe the role of reactants and products in chemical reactions. Explain the relationship between enzymes and activation energy. Explain how oxidation and reduction reactions are linked.

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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. What is plasma?

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy Chapter 2 Energy and Chemical Reactions Reactants are substances that enter chemical reactions. Products are substances produced by chemical reactions.

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 Energy and Chemical Reactions Section 2 Energy

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 Activation Energy and Chemical Reactions Section 2 Energy

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Objectives Describe the structure of a water molecule. Explain how 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.

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Polarity Water is considered to be a polar molecule due to an uneven distribution of charge. The electrons in a water molecule are shared unevenly between hydrogen and oxygen.

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Hydrogen Bonding A hydrogen bond is 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.

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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. –Adhesion is the attractive force between two particles of different substances, such as water molecules and glass molecules.

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 Comparing Cohesion and Adhesion Section 3 Water and Solutions

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Solutions A solution consists of a solute dissolved in a solvent.

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Acids and Bases Ionization of Water –Water ionizes into hydronium ions (H 3 O + ) and hydroxide ions (OH – ).

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Acids and Bases, continued Acids –Acidic solutions contain more hydronium ions than hydroxide ions.

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Acids and Bases, continued Bases –Basic solutions contain more hydroxide ions than hydronium ions.

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 Bases Section 3 Water and Solutions

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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.

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 The pH Scale Section 3 Water and Solutions

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Acids and Bases, continued Buffers –Buffers are chemicals that neutralize the effects of adding small amounts of either an acid or a base to a solution.

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 2 pH Section 3 Water and Solutions

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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 Standardized Test Prep Chapter 2

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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 Standardized Test Prep Chapter 2

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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 Standardized Test Prep Chapter 2

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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 Standardized Test Prep Chapter 2

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 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 Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 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 Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

60. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 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 Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

61. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 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 Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

62. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. What is an aqueous solution that contains more hydroxide ions than hydronium ions called? A. a gas B. a base C. a solid D. an acid Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

63. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. What is an aqueous solution that contains more hydroxide ions than hydronium ions called? A. a gas B. a base C. a solid D. an acid Chapter 2 The graph below shows the energy in a chemical reaction as the reaction progresses. Use the graph to answer the questions that follow. Standardized Test Prep

64. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 6. Oxidation : loss :: reduction : F. win G. gain H. take J. forfeit Chapter 2 Standardized Test Prep

65. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 6. Oxidation : loss :: reduction : F. win G. gain H. take J. forfeit Chapter 2 Standardized Test Prep

66. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 7. The covalent bonds on the water molecule depicted in the picture above has partial positive charges on the hydrogen atom and a partial negative charge on the oxygen atom. What do the partial positive and partial negative charges on this water molecule mean? A. Water is an ion. B. Water is a polar molecule. C. Water needs a proton and two electrons to be stable. D. Oxygen atoms and hydrogen atoms have opposite charges. Chapter 2 The illustration below is a space-filling model of water. Use the model to answer the following question. Standardized Test Prep

67. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 7. The covalent bonds on the water molecule depicted in the picture above has partial positive charges on the hydrogen atom and a partial negative charge on the oxygen atom. What do the partial positive and partial negative charges on this water molecule mean? A. Water is an ion. B. Water is a polar molecule. C. Water needs a proton and two electrons to be stable. D. Oxygen atoms and hydrogen atoms have opposite charges. Chapter 2 The illustration below is a space-filling model of water. Use the model to answer the following question. Standardized Test Prep

68. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response Covalent bonding is a sharing of electrons between atoms. Why do some atoms share electrons? Chapter 2 Standardized Test Prep

69. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response, continued Covalent bonding is a sharing of electrons between atoms. Why do some atoms share electrons? Answer: Sharing electrons achieves a stable number of electrons in the orbitals that correspond to the highest energy level for each atom. Chapter 2 Standardized Test Prep

70. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Extended Response Pure water contains equal numbers of hydronium ions and hydroxide ions and is therefore a neutral solution. Part A What is the initial cause of the dissociation of water molecules into hydrogen and hydroxide ions? Explain the process. Part B After water dissociates, hydronium ions are formed. Explain this process. Chapter 2 Standardized Test Prep

71. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Extended Response, continued Answer: Part A Water molecules collide as they move about. Some collisions result in the loss of a hydrogen nucleus. Thus, the water molecule gives rise to a hydrogen ion and a hydroxide ion. Part B The hydrogen ion from the initial dissociation of water combines with another water molecule to form a hydronium ion. Chapter 2 Standardized Test Prep

72. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Elements and Atoms

73. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Elements and Atoms

74. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Composition of Matter Chapter 2 Compounds

75. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy Chapter 2 Energy and Matter

76. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Water and Solutions Chapter 2 Hydrogen Bonding