1. Go to Section: What’s the Matter? 1. Give an example of solid matter. 2. Give an example of liquid matter. 3. Give an example of gaseous matter. 4. Is all matter visible? 5. Does all matter take up space? Section 2-1 Interest Grabber

2. Go to Section: 2–1The Nature of Matter A.Atoms B.Elements and Isotopes 1.Isotopes 2.Radioactive Isotopes C.Chemical Compounds D.Chemical Bonds 1.Ionic Bonds 2.Covalent Bonds 3.Van der Waals Forces Section 2-1 Section Outline

3. Go to Section: 2-1a. Atoms Basic units of matter. – Once previously thought to be indivisible. “atomos” – Unable to cut Democritus – 2500 years ago; thought up the idea of atoms and named them 100 million atoms in a row is about 1cm long

4. Go to Section: Subatomic Particles: Protons – positively charged particles; part of the nucleus Neutrons – carry no charge; have mass; are part of the nucleus Electrons – negatively charged particles the surround the nucleus

5. Go to Section: Protons and neutrons have about the same mass. Bound together in the center of the atom (nucleus) The electron is much smaller (1/1840 of the size of a proton). They are constantly in motion. They are attracted to the positive charge of the nucleus but remain outside because of their energy.

6. Go to Section: Atoms are considered to be neutral because there is an equal number of protons and electrons. (opposite charges)

7. Go to Section: 2-1b Elements and Isotopes Elements are pure substances that consist entirely of one type of atom. Elements are represented by a one or two letter symbols and presented on the Periodic Table.

8. Go to Section: 6 C Carbon 12.011 Section 2-1 An Element in the Periodic Table

9. Go to Section: The number above the symbol is called the atomic number. It tells you the number of protons in an atom and consequently, the electrons. The bottom number is called the mass number. It tells the mass of the nucleus, or the mass of protons and neutrons.

10. Go to Section: 2-1B1 Atoms of an element can have different numbers of neutrons. If they do differ in the number of neutrons, they are called isotopes. We identify isotopes by their mass number.

11. Go to Section: Atomic mass is a weighted average of the different isotopes. All isotopes have the same chemical properties because they have the same number of electrons.

12. Go to Section: 2-1 B2. Some isotopes are radioactive, meaning their nuclei are unstable and break down at a constant rate. Practical uses: fossil / rock dating Treating cancer and killing bacteria Used as tracers to follow movements of substances.

13. Go to Section: Nonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-14 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 8 neutrons 6 electrons 6 protons 7 neutrons Section 2-1 Figure 2-2 Isotopes of Carbon

14. Go to Section: 2-1C – Chemical Compounds A chemical compound is a substance formed by the chemical combination of two or more elements in definite proportions. The physical and chemical properties of a compound are very different from the elements that form it. (sodium and chlorine page 37)

15. Go to Section: 2-1D Chemical Bonds Bonds hold the atoms in compounds together. The formation of bonds involves electrons that surround each nucleus. The electrons involved with bonding are called valence electrons. The main types of bonds are ionic and covalent.

16. Go to Section: 2-1D1 – Ionic Bonds An ionic bond is formed when one or more electrons are transferred from one atom to another. An atom that loses an electron becomes positive. An atom that gains an electron becomes negative.

17. Go to Section: The positively and negatively charged atoms are now called ions. Oppositely charged ions have a strong attraction called an ionic bond.

18. Go to Section: Sodium atom (Na)Chlorine atom (Cl)Sodium ion (Na + )Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1 Section 2-1 Figure 2-3 Ionic Bonding

19. Go to Section: Sodium atom (Na)Chlorine atom (Cl)Sodium ion (Na + )Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1 Section 2-1 Figure 2-3 Ionic Bonding

20. Go to Section: 2-1 D2 – Covalent Compounds Covalent bonds occur when electrons are being shared between two or more atoms. You can have single, double, or triple bonds.

21. Go to Section: The structure that results when atoms are joined together by covalent bonds is called a molecule. A molecule is the smallest unit of most compounds.

22. Go to Section: Sharing among covalent bonds is not always equal. The unequal sharing causes slight positive and negative attractions. The attractions are called van der Waal forces.

23. Go to Section: Energy Levels Distinct regions around the nucleus where electrons are found 1. Octet Rule – the outermost level (for stability purposes) will not hold more or less than 8 electrons

24. Go to Section: 2–2 Properties of Water A.The Water Molecule 1.Polarity 2.Hydrogen Bonds B.Solutions and Suspensions 1.Solutions 2.Suspensions C.Acids, Bases, and pH 1.The pH Scale 2.Acids 3.Bases 4.Buffers Section 2-2 Section Outline

25. Go to Section: 2a – The Water Molecule Water is the single most abundant compound in most living things. Unique: Water expands as it freezes which changes its volume and explains why ice floats on water.

26. Go to Section: 2A-1 Polarity Water is a neutral compound; 10 protons and 10 electrons Oxygen has a greater attraction for electrons than hydrogen does. It is polar because there is an uneven distribution between the oxygen and hydrogen atoms.

27. Go to Section: 2A-2 Hydrogen Bonds They form between the positive charge of hydrogens and the negative charge of the oxygen on the adjacent molecule. Not as strong as ionic or covalent, but the strongest between adjacent molecules. Can have up to 4 hydrogen bonds at any time, which gives water its properties.

28. Go to Section: continued a.Cohesion – attraction between molecules of the same substance; ex. Drops of water on the surface; why insects can walk on water b.Adhesion - attraction of molecules of different substances; meniscus of water- attracts to glass

29. Go to Section: 2B. Intro A mixture is a combination of substances that are not chemically bonded and they do not have a set ratio

30. Go to Section: 2B-1 Solutions A uniform mixture of two or more substances Mixed so well that you cannot see the difference between the substances Made of two Components: 1. solute – dissolved substance. 2. solvent – dissolving substance (water = universal solvent)

31. Go to Section: 2B -2 Suspensions Mixtures of water and undissolved materials. EX. Blood – solution because it contains water which dissolve many compounds, Suspension because it contains cells that do not settle out.

32. Go to Section: 2C-1 pH scale A standard measurement of the concentration of the H+ ions in a solution Numbered from 0-14 0=highly acidic; 14=highly basic Each step represents a factor of 10

33. Go to Section: 2C-2 Acids Any compound that forms H+ ions in solution Strong acids usually have a pH of 0-3

34. Go to Section: 2c-3 Bases Contain lower concentrations of H+ ions than pure water (produces OH- ions) Strong bases usually have a pH of 11-14

35. Go to Section: 2C-4 Buffers Fluids in the human body must have a pH between 6.5 and 7.5 (except stomach acid – 2) Buffers are weak acids or bases that react with strong acids or bases to prevent sharp, sudden changes in pH

36. Go to Section: Oven cleaner Bleach Ammonia solution Soap Sea water Human blood Pure water Milk Normal rainfall Acid rain Tomato juice Lemon juice Stomach acid Neutral Increasingly Basic Increasingly Acidic Section 2-2 pH Scale

37. Go to Section: Cl - Water Cl - Na + Water Na + Section 2-2 Figure 2-9 NaCI Solution

38. Go to Section: Section 2-2 Figure 2-9 NaCI Solution Cl - Water Cl - Na + Water Na +

39. Go to Section: 2–3Carbon Compounds A.The Chemistry of Carbon B.Macromolecules C.Carbohydrates D.Lipids E.Nucleic Acids F.Proteins Section 2-3 Section Outline

40. Go to Section: 2-3A The Chemistry of Carbon Carbon has four valence electrons allowing it to bond with many other elements, including itself Carbon can form many different large and complex structures (diamonds, graphite)

41. Go to Section: 2-3B Macromolecules 1.Monomer – small building block of organic molecules 2.Polymer – linking of 2 or more monomers 3.When a polymer becomes thousands of monomers long, it is also called a macromolecule

42. Go to Section: 2-3C Carbohydrates Compound composed of carbon, hydrogen, and oxygen 1:2:1 ratio Supplies immediate energy for all cell activities Extra sugar is stored as complex carbohydrates called starches

43. Go to Section: Carbohydrates continued… Sugars: 1.Monosaccharides – simplest carbs; contain3,5 or 6 carbon atoms; glucose, fructose 2.Disaccharides – sugars made of two covalently bonded monosaccharides; sucrose, lactose

44. Go to Section: Continued 3. Polysaccharides – giant polymers that consist of thousands of linked monosaccharides; glycogen 4. Plant starch – used to store extra sugar and give plants strength and flexibility; cellulose

45. Go to Section: 2-3D Lipids Do not dissolve in water; made of carbon and hydrogen atoms Types: 1. fats – compounds composed of glycerol and fatty acids; energy and storage 2. Phospholipids – contain phosphate; cell membranes

46. Go to Section: continued 3. Steroids – lipids composed of four linked rings of carbon atoms; chemical messengers Cholesterol Hormones – special chemicals produced in one part of the body that controls the functions of other parts of the body

47. Go to Section: Lipids continued…. 4. Waxes – composed of fatty acids and alcohols; waterproofing The chemistry of fats: 1. Fatty acid – compounds consisting of a chain of carbon atoms with an acid group at one end

48. Go to Section: Fats continued… 2. (2) Types of Fats a.Saturated fats – the molecules is completely saturated with hydrogen atoms; solid at room temperature b.Unsaturated fats – the molecule contains double bonds where hydrogens are in saturated fats; liquid at room temp

49. Go to Section: 2-3E – Nucleic Acids 1.Large complex molecules composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus; store and transmit hereditary information

50. Go to Section: 2. Polymers of nucleotides A nucleotide is a 5-carbon sugar, a nitrogen containing base, and a phosphate group

51. Go to Section: 3. (2) Types of Nucleic Acids DNARNA NameDeoxyribonucleic Acid Ribonucleic Acid SugarDeoxyriboseRibose BasesA, G, C, TA, G, C, U ShapeDouble StrandedSingle Stranded FunctionControls Cell Activites Builds Proteins

52. Go to Section: Adenine – DNA, RNA Guanine – DNA, RNA Cytosine – DNA, RNA Thymine - DNA Uracil - RNA

53. Go to Section: 2-3 F Proteins Compounds composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur Structure: (1.) Amino acids – a compound that contains an amino group, a carboxyl group, and a side group

54. Go to Section: Protein structure continued: a.The side group determines the type of amino acid b.All proteins are polymers of amino acids c.20 amino acids d.Held together by peptide bonds; polypeptide chain (covalent bond between amino acids) e.Sequence is very important

55. Go to Section: Proteins continued: Functions of proteins: a.Movement – muscles b.Structure – connective fibers (collagen, keratin) c.Biochemical control – enzymes d.Transport – hemoglobin

56. Go to Section: e. Storage – storage of amino acids in baby animals f. Regulation - insulin (controls sugar in the blood) g. Defense - antibodies

57. Go to Section: Carbon Compounds include that consist of which contain that consist of which contain Section 2-3 Concept Map CarbohydratesLipidsNucleic acidsProteins Sugars and starches Fats and oilsNucleotidesAmino Acids Carbon, hydrogen, oxygen Carbon, hydrogen, oxygen Carbon,hydrogen, oxygen, nitrogen, phosphorus Carbon, hydrogen,oxygen, nitrogen,

58. Go to Section: 2–4Chemical Reactions and Enzymes A.Chemical Reactions B.Energy in Reactions 1.Energy Changes 2.Activation Energy C.Enzymes D.Enzyme Action 1.The Enzyme-Substrate Complex 2.Regulation of Enzyme Activity Section 2-4 Section Outline

59. Go to Section: 2-4 A Chemical Reactions Chemical reactions – process that changes one set of chemicals into another set of chemicals All things that happen in an organisms are dependent on chemical reactions EX. Growth, interaction with the environment, reproduction, movement

60. Go to Section: Parts of a chemical reaction 1.Reactants – elements or compounds that enter into a reaction 2.Products – elements or compounds produced by a chemical reaction

61. Go to Section: 2-4 B Energy in Reactions Energy Changes: 1.(exothermic) Chemical reactions that release energy often occur spontaneously. Energy released as heat, light, or sound 2. (endothermic) Chemical reactions that absorb energy will not occur without a source of energy.

62. Go to Section: Animals and plants must obtain energy either by food or sunlight. Activation energy – the energy needed to get a reaction started

63. Go to Section: 2-4 C Enzymes 1.Some chemical reactions are too slow to be useful. (The required activation energy is too high.) 2.Catalyst – substance that speeds up a chemical reaction without changing the reactants or products by lowering the activation energy

64. Go to Section: Enzymes – proteins that act as biological catalysts There are specific enzymes for specific reactions.

65. Go to Section: 2-4 D Enzyme Action The Enzyme-Substrate Complex 1.Enzymes provide a place for the reactants (substrates) and the products of a reaction to meet so they can react. 2.Substrates bond to the active site on the enzyme.; Lock and Key

66. Go to Section: Regulation of Enzyme Activity 1.How and when Enzymes work a. certain pH b. certain temperature c. proteins can turn enzymes on or off

67. Go to Section: 2. Regulation of Body Activities a.Chemical pathways b. Making materials the cells need c. Releasing energy d. Transferring information