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Question of the Day

Question of the Day. Water is called a polar molecule because: a. H has a negative charge and O has a positive charge b. O has a negative charge and H has a positive charge c. it has a net charge of zero d. it freezes at 0 degrees C. DO NOW Sept 25.

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Question of the Day

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  1. Question of the Day • Water is called a polar molecule because: • a. H has a negative charge and O has a positive charge • b. O has a negative charge and H has a positive charge • c. it has a net charge of zero • d. it freezes at 0 degrees C

  2. DO NOW Sept 25 • List as many facts about water as you can. • Think Biology when you do this. • We all know water is cool and refreshing and sold in bottles.

  3. DO NOW ANSWERED • We will learn all about the properties of water in Section 2-2.

  4. AGENDA Sept 25 • BIG QUESTION: Why is water so critical to life? • 1. QOD • 2. DO NOW • 3. Properties of Water • 4. Closing Thoughts and Homework

  5. Chapter 2 Sections 2 - 4 The Chemical Basis of Life

  6. 2-2: Properties of Water • Liquid on the Earth’s surface • has physical and chemical properties found in no other material • covers 75% of Earth • has an uneven distribution of electrons and is slightly charged on each end

  7. The BLUE Planet • Water is the single most abundant compound in most living things. • Liquid at room temperature. • Expands when it freezes. • Floats in a solid state.

  8. Unique Properties of Water • Water is a POLAR molecule. • Can attract each other. • Not always pure and can be found as part of a mixture. • Can react to form ions.

  9. Water is a POLAR Molecule • Water carries a slightly negative charge on the O atom and a slightly positive charge on the H atoms. Acts like a magnet. Polarity in water is due to uneven distribution of electrons between oxygen and hydrogen atoms.

  10. Attraction of Opposite Charges • Cohesion is the attraction between molecules of the same substance. • Hydrogen bonding. • Adhesion is the attraction between • molecules of different substances.

  11. Question of the Day • When sand and sugar are shaken together in a test tube, which of the following is formed? • A. compound • B. mixture • C. solution • D. suspension

  12. DO NOW Sept 26 • Explain why water molecules can attract each other.

  13. DO NOW ANSWERED • Water is a polar molecule. • The O atom has a slightly negative charge and the H atom has a slightly positive charge. • Water molecules attract each other through this difference in charge. • Hydrogen bonding holds these molecules together.

  14. AGENDA Sept 26 • BIG QUESTION: What are acidic and basic solutions? • 1. QoD • 2. DO NOW • 3. Continue Section 2-2: Mixtures and pH • 4. Classwork/Review of Key Concepts • 5. Closing Thoughts and Homework • QUIZ on MONDAY Sept 30 • Sections 2-1 and 2-2

  15. How does a gecko stick to the surface of a wall? • Electrons in covalent bonds are equally shared. • Rapid movement of electrons can still create tiny positive or negative charges.

  16. The Answer… • Geckos can defy gravity. • Thousands of tiny hair-like projections are divided into many fibers. • A gecko’s foot can come in contact with an extremely large surface of the wall at a molecular level. Van der Waals Forces are slight attractions between the oppositely charged regions of nearby molecules.

  17. Water Often forms Mixtures • a material composed of two or more elements or compounds that are physically mixed together but not chemically combined • Sugar and sand • Earth’s atmosphere is a mixture of gases • slight charges of a water molecule make them good at forming mixtures

  18. Two Important Water Mixtures • solution: a homogeneous mixture in which one substance is dissolved in another • solvent: substance that does the dissolving • solute: the substance that is dissolved • water is the greatest solvent because of its charges • suspension: mixture containing nondissolved particles distributed within a solid, liquid, or gas

  19. Acids and Bases • acids: compounds that have higher concentrations of H+ ions than pure water. • Form H+ ions in a solution • Have a pH lower than 7 • HCl (Hydrochloric Acid) is a strong acid • bases: compounds that have lower concentrations of H+ ions than pure water. • Form OH- ions in solution • Have a pH higher than 7 • Bleach is a strong base Buffers: weak acids or bases that prevent sharp changes in pH levels to help maintain homeostasis.

  20. The pH Scale • pH scale: a measurement system that indicates the concentration of hydrogen ions in solution. • neutralization reaction: reaction that occurs when H+ ions of a strong acid react with the OH- ions of a strong base • form water and a salt.

  21. Question of the Day • A compound that produces H+ ions in solutions is called a • A. Salt • B. Base • C. Polymer • D. Acid

  22. DO NOW Sept 27 • How much more acidic is a solution having a pH 9 compared to a solution having a pH 12?

  23. DO NOW Answered • The answer is 1000 times. • How do you determine the answer?

  24. AGENDA Sept 27 • BIG QUESTION: How can the pH values of different substances be measured? • 1. QoD • 2. DO NOW • 3. H+ Concentrations. • 4. pH Lab Investigation – Measuring pH in Common Substances • 5. Review and Homework: pH Review Questions • QUIZ on MONDAY SEPT 30 Sections 2-1 and 2-2

  25. Relative Concentrations of H+ Ions • Concentrations of acids and bases are measured in powers of 10. • Used to represent the relative strength of an acid or base compared to another one. • A substance with a pH of 4 is 100 times more acidic than a substance with a pH of 6 • 100 times is equal to 102 • How much more acidic is a solution with pH 3 compared with a solution having a pH of 8?

  26. Using Indicators to Measure pH

  27. AGENDA Sept 30 • BIG QUESTION: What are the functions of organic molecules? • 1. CHAPTER 2 Quiz – Sections 2-1 and 2-2 • Begin reading Section 2-3 when finished with Quiz • 2. Hand in your pH Labs • 3. The Chemistry of Carbon and Macromolecules • 4. Homework and Closing Thoughts

  28. 2-3 Chemistry of Carbon OrganicCompounds • Compounds containing C • Forms covalent bonds that are strong and stable • 4 single covalent bonds • carbon can form chains of almost unlimited length by bonding to other carbon atoms • Single, double, or triple covalent • can form rings

  29. InorganicCompounds • do not contain carbon • one exception is CO2 • living things contain many inorganic compounds • water, oxygen, carbon dioxide, and salt are all inorganic compounds

  30. Polymerization • process in which large compounds are constructed by joining together smaller compounds • monomers: smaller units which join together to form: • polymers: larger compounds which join together to form: • macromolecules: giant molecules made of hundreds or thousands of smaller molecules.

  31. Four Groups of Organic Compounds in Living Things • Carbohydrates are the main source of energy for living things. • made of carbon, hydrogen, and oxygen atoms • C:H:O 1:2:1 Ratio • simplest carbohydrates are monosaccharides • glucose, galactose (milk), and fructose (fruits) • Breakdown of sugars supplies immediate energy for all cell activities

  32. Question of the Day Oct 1 • Which of the following is not an organic compound found in living things? • A. Proteins • B. Lipids • C. Carbon dioxide • D. Nucleic Acids

  33. DO NOW Oct 1 • CLOSE YOUR NOTEBOOKS. • Explain how macromolecules are formed.

  34. DO NOW ANSWERED Oct 1 • Polymerization is the process which builds larger compounds from smaller compounds. • Monomers Polymers Macromolecules

  35. AGENDA Oct 1 • Big Question: What are the functions of organic compounds? • 1. QoD • 2. DO NOW • 3. Carbohydrates and Lipids • 4. Review Chapter 2 Quiz • 5. Homework and Closing Thoughts Remember to STUDY your notes everyday.

  36. Also used for structural purposes in plants and some animals. • Extra sugar stored as complex carbohydrates known as starches. • polysaccharide: a large molecule that is formed by joining together many monosaccharide units • Glycogen (animal starch) stores excess sugar. • Released from liver into blood when sugar is low. • Glycogen in muscles supplies energy for movement. • Plants also store excess sugar in plant starch. • Cellulose is used in plants as tough, flexible fibers for strength and rigidity. • Major component of wood and paper.

  37. Dehydration and Hydrolysis • Opposite reactions that build up or breakdown molecules. • Dehydration reaction is the combining of two smaller molecules to form one larger molecule resulting in the loss of water. • Hydrolysis reaction is the breaking down of one larger molecule into two smaller molecules by the addition of water.

  38. 2. Lipids • Generally not soluble in water • Made up mostly of C and H atoms • Fats, oils, and waxes • store energy, form membranes, and used as chemical messengers • Steroids are chemical messengers in the body. • Formed from 2 or 3 fattyacids combining with a glycerol

  39. QUESTION OF THE DAY • Lipids are made up of • A. Sugars and starches • B. Fatty acids and glycerol • C. Glycogen and Cellulose • D. Glucose and Glycerol

  40. DO NOW Oct 2 • What type of molecule is glycogen? • Explain why glycogen is important in the human body.

  41. DO NOW ANSWERED • Glycogen is a polysaccharide. • It is an animal starch that stores excess energy. • It is released by the liver when blood sugar is low to provide a constant supply of energy to the body for cellular activities.

  42. AGENDA Oct 2 • Big Question: What are the functions of organic compounds? • 1. QoD • 2. DO NOW • 3. Review Dehydration and Hydrolysis Reactions • 4. Continue 2-3: Lipids and Nucleic Acids • 5. Homework and Closing Thoughts • STUDY YOUR NOTES EVERY DAY • BIO PARTY!!! Hosted by ???

  43. saturated fat: a fatty acid where every carbon atom is joined to another carbon atom by a single bond and contains the maximum number of hydrogen atoms • Meats and dairy products • unsaturated fat: a fatty acid where a pair of carbon atoms are joined by a double bond. • Liquid at room temperature. • Olive oil • polyunsaturated fat: a fatty acid that contains several double bonds • Cooking oils such as canola, soy and peanut.

  44. 3. Nucleic Acids • composed of C, O, H, N, and P • made up of monomers called nucleotides • Nucleotides have 3 basic parts • 5-carbon sugar • nitrogenous base • Phosphate group • Joined together by covalent bonds

  45. Question of the Day • Which of the following is not a unique property of water? • A. It is a liquid at room temperature. • B. Molecules can attract each other. • C. It can be part of a mixture. • D. It can react to form ions.

  46. DO NOW CHALLENGE • ARE YOU READY? • Close your Notebooks • And today’s contestants are….

  47. DO NOW CHALLENGE • Jake, Jillian, and Adam N. • Draw a diagram to represent a nucleotide. • Label its three basic parts.

  48. Nucleic Acids • Nucleic acids store and transmit hereditary or genetic information. • Two kinds: • DNA (Deoxyribonucleic acid) • Contains deoxyribose sugar • RNA (Ribonucleic acid) • Contains Ribose Sugar

  49. 4. Proteins • Contain C, N, O, and H • made up of monomers called aminoacids: contain an amino group on one end and a carboxyl group on the other • Covalent bonds form between identical sections. • 20 different amino acids • peptide bond: a covalent bond that joins two amino acids • Amino group (-NHH) bonded to a Carboxyl group (-COOH)

  50. Question of the Day • Why is battery acid considered a strong acid? • A. It forms H- ions in solution • B. It forms OH- ions in solution • C. It has a pH of approximately 13.8 • D. It has a pH of approximately 1.5

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