INTRO TO CHEMISTRY

1. INTRO TO CHEMISTRY COOMES PRE-AP BIOLOGY

2. WHAT ARE ELEMENTS? Cannot be broken down 92 naturally occurring 25 required by living organisms CHON (Carbon,Hydrogen,Oxygen,Nitrogen) make up 96.3% of human body Atom: smallest unit of an element

4. COMPOUNDS Composed of 2 or more elements Examples: Sodium Chloride, Water, Carbon Dioxide

5. SUBATOMIC PARTICLES • Atoms are made of 3 types of particles: • Protons: positive charge, in nucleus • Neutrons: neutral charge, in nucleus • Electrons: negative charge, outside of nucleus in electron cloud (orbitals)

6. PERIODIC TABLE Contains all of the elements, arranged by class (metals, non-metals, noble gases, rare earths) and atomic number Atomic number: Number of protons Isotope: Elements with same atomic number but different atomic mass (different number of neutrons)

8. IONIC BOND • Ion: charged atom that has lost or gained electrons • Ionic bond: eletron is transferrred • Example: Sodium chloride (table salt

9. Table Salt Ionic bond Crystal lattice structure: very stable & strong

10. COVALENT BONDS Electrons are shared between atoms Single bond: C-C Double bond: C=C Triple bond:C=C

11. COVALENT BONDS When eletrons are unequally shared, the molecule is POLAR When electrons are shared equally, the molecule is NONPOLAR Nonpolar molecules are neutral Hydrophobic • Polar molecules are charged molecules • Hydrophilic

12. HYDROGEN BONDING • Contribute to unique properties of water • Relatively weak bonds

13. COHESION • Linking of like molecules • Water Strider (Surface Tension) • Adhesion • Water on windshield • Transpiration • Water moves up the xylem (thin tubes) and evaporates from stomata • Cling together by cohesion, “adhere” to xylem walls

17. HIGH SPECIFIC HEAT • Amount of heat required to raise or lower temperature by 1̊ C • Moderation of temperature • Makes ocean temp relatively stable and able to support more animal & plant life

18. INSULATION OF WATER BY FLOATING ICE Water is less dense as a solid

20. UNIVERSAL SOLVENT Able to dissolve both acids & bases

21. PROPERTIES OF WATER LAB • Cohesion • Adhesion • Surface Tension • Hydrophobic/Hydrophilic Interactions • Polar vs. Nonpolar

22. pH Scale • Acids: excess Hydrogen Ions (H+) • Bases: excess Hydroxide OH- • Buffers minimize change in pH • Accept excess Hydrogen ions or donate depleted Hydrogen ions • Ex: Carbonic Acid (H2CO3): buffer in living systems • Blood plasma, ocean

24. pH Lab What did we do? Control? Hypotheses? How would you determine pH without the color card?

25. BIOMOLECULES PRE-AP BIOLOGY

26. BIOCHEMISTRY • Chemistry of living things organized around CARBON (organic chemistry) • Methane: simplest carbon compound • Major component of natural gas

27. HYDROCARBONS • Molecules made of only hydrogen &carbon • 2 ways to represent structures: • Model • Formula

28. COVALENT BONDS • Share electrons • Single, double, triple bond • Hydrogen: 1 • Oxygen: 2 • Nitrogen: 3 • Carbon: 4

29. FUNCTIONAL GROUPS • R=hydrocarbon group • Alcohol • Carboxyl • Amines

30. ALCOHOL • Functional group: (R-OH) • Hydroxide: base • R-OH: makes alcohols more soluble in water than similar molecules • Methanol: wood alcohol (antiseptic) • Ethanol: beverage Methanol Ethanol

31. CARBOXYL • R-COOH (acid) • Releases hydrogen ions in water • “Organic acids”

32. AMINES • R-NH2 • Organic bases because they accept hydrogen ions from acids

33. CARBOHYDRATES • Provide energy for cells when broken down • Organic compounds made of Carbon, Hydrogen, & Oxygen • Most have 2 atoms of hydrogen for every oxygen • Classified by # sugar units • Example: pasta

34. MONOSACCHARIDES • Carbohydrate made of one sugar unit • Most common simple sugar: glucose • Primary cellular fuel of most organisms • The building blocks of larger CHO • Combined through biosynthesis

35. GLUCOSE

36. GALACTOSE

37. FRUCTOSE (fruit sugar)

38. 2 Monosaccharides=1 Disaccharide Sucrose (table sugar): glucose + fructose

39. Malt Sugar=Glucose + Glucose

40. Milk Sugar=Glucose + Galactose

41. POLYSACCHARIDE • >2 monosaccharides • Broken down through hydrolysis • Cellulose • Starch • Glycogen

42. CELLULOSE • Major part of leafy vegetables, whole wheat, carrots, & other plant material in your diet • Often called ‘fiber’ or ‘roughage’ • Body cannot break it down into any glucose molecules • No energy received from fiber • More fiber seems to decrease the risk of cancer in the digestive tract • Only digested by microorganisms & a few wood-eating beetles • Animals that eat grass & leaves depend on these microorganisms in their digestive tracts to digest cellulose for them • Important to diet

44. STARCH • 100’s-1000’s of glucose molecules • Examples: potatoes, pasta

46. GLYCOGEN • Like starch but for animals • Animals store energy as glycogen • Stored in liver & muscles

47. LIPIDS • Non-polar organic molecules • Do not dissolve in water • Examples: vegetable oil, butter, furniture wax • Functions: • Barrier b/t cell & environment • Ex: lipid bilayer, blubber in whales • Store energy • Fatty acids: building blocks of lipids

49. SATURATED FAT • Maximum # hydrogen atoms attached to it (SOLID) • Non-polar • Insoluble in water • No C=C bonds

50. UNSATURATED FAT • Molecules with double bonds • C=C • LIQUID • POLYUNSATURATED: >2 C=C