Slide 1 / 97. Organic Chemistry: Carbon and the Molecular Diversity of Life

Transcription

1 Slide 1 / 97 Organic Chemistry: Carbon and the Molecular Diversity of Life

2 Slide 2 / 97 Organic Chemistry Organic chemistry is the study of carbon compounds Organic compounds range from simple molecules to colossal ones. Most organic compounds contain hydrogen atoms in addition to carbon atoms. Compounds containing only carbon and hydrogen are called hydrocarbons; they are commonly used as a fuel source.

3 Slide 3 / 97 Biological Molecules Carbon is the backbone of biological molecule. Carbon has the ability to form long chains. This property allows the formation of large biomolecules (such as proteins, lipids, carbohydrates, and nucleic acids).

4 Slide 4 / 97 Carbon Carbon has four valence electrons to make covalent bonds Carbon atoms can form diverse molecules by bonding to four other atoms Recall that electron configuration is the key to an atom s characteristics because it determines the kinds of bonds and number of bonds an atom will form with other atoms

5 Slide 5 / 97 1 Organic chemistry is a science based on the study of. A B C D compounds that can only be made by living cells. vital forces interacting with matter. carbon compounds. water and its interaction with other kinds of molecules.

6 Slide 6 / 97 2 Which property of the carbon atom allows it to bond with many different elements? A B C D E Carbon has 6 to 8 neutrons. Carbon has 4 valence electrons. Carbon forms ionic bonds. A and C only A, B, and C

7 Slide 7 / 97 3 How many electron pairs does carbon share in order to complete its valence shell? A 1 B 2 C 3 D 4 E 8

8 Slide 8 / 97 4 What type/s of bond/s does carbon have a tendency to form? A B C D E Ionic Hydrogen Covalent A and B A, B and C

9 Slide 9 / 97 Hydrocarbons Hydrocarbons are compounds made up of carbon and hydrogen atoms Aliphatic hydrocarbons: compounds with carbon atoms connected in a straight chain Aliphatic compounds consist of three classes of compounds: Alkanes Alkenes Alkynes Aromatic hydrocarbons: compounds with carbon atoms connected in cyclic (ringed) structures that have an odor

10 Slide 10 / 97 Aliphatic hydrocarbons: Alkanes Hydrocarbon chains where all the bonds between carbons are SINGLE bonds They are also known as saturated hydrocarbons. They are saturated with hydrogens. Name uses the ending -ane Examples: Methane, Propane, Butane, Octane

11 Alkanes Slide 11 / 97

12 Alkanes Slide 12 / 97 The general formula C n H 2n+2 n = number of carbon atoms CH 4 C 2 H 6 C 3 H 8 Methane Ethane Propane Hexane Heptane Octane C 4 H 10 Butane Nonane C 5 H 12 Pentane Decane

13 Slide 13 / 97 Straight Chain Alkanes Straight chain alkanes are alkanes that have all their carbon atoms connected in a row. These are structural formulas. CH 3 -CH 2 -CH 3 This is a condensed formula for propane.

14 Slide 14 / 97 Branched Chain Alkanes Branched chain alkanes are alkanes that have a branching connection of carbons. For example, butane has the formula C 4 H 10. Shown below are the straight chain and branched forms of butane. CH 3 -CH 2 -CH 2 -CH 3 Straight chain butane Branched chain butane

15 Slide 15 / 97 Alkanes Hydrocarbons are non polar, since the difference in electronegativity between C and H is below 0.5. Note that larger molecules are more polarizable and therefore have stronger London dispersion forces which increases boiling point.

16 Slide 16 / 97 5 What is the reason why hydrocarbons are not soluble in water? A B C D E The majority of their bonds are polar covalent C-H linkages The majority of their bonds are nonpolar covalent C-H linkages They are hydrophilic They exhibit considerable molecular complexity and diversity They are lighter than water

17 Slide 17 / 97 6 Gasoline and water do not mix because gasoline is. A B C D E less dense than water less viscous than wtaer nonpolar and water is polar volatile and water is not polar and water is nonpolar

18 Slide 18 / 97 7 Which substance would be the most soluble in gasoline? A water B sodium nitrate, NaNO 3 C hydochloric acid, HCl D hexane, C 6 H 14 E sodium chloride, NaCl

19 Slide 19 / 97 Aliphatic hydrocarbons: Alkenes Alkenes have at least one double bond between two carbon atoms. General formula: C n H 2n where n = # of carbon atoms The name uses the ending -ene. The simplest alkenes are: C 2 H 4 Ethene (from 2-carbon parent, ethane) C 3 H 6 Propene (from 3-carbon parent, propane) Ethene

20 Slide 20 / 97 Aliphatic hydrocarbons: Alkynes Alkynes have at least one triple bond between two carbon atoms. General formula: C n H 2n-2 where n = # of carbon atoms The name uses the ending -yne. The simplest alkynes are: C 2 H 2 Ethyne (commonly known as acetylene) C 3 H 4 Propyne or propylene Ethyne

21 Slide 21 / 97 Representing Aliphatic Hydrocarbons Ball and stick model Space filling model Structural formula Molecular formula

22 Slide 22 / 97 Cycloalkanes Carbon can also form ringed structures. Five- and six-membered rings are most stable. They can take on conformations in which their bond angles are very close to the tetrahedral angle. Smaller rings are quite strained

23 Slide 23 / 97 Aromatic hydrocarbons They have benzene ring structure ( hexagon) and have particular aroma associated with it. CH 3 Benzene Toluene ( methyl benzene)

24 Slide 24 / 97 8 Hydrocarbons A B C D E are polar. are held together by ionic bonds. contain nitrogen. contain only hydrogen and carbon atoms. are held together by hydrogen bonds.

25 Slide 25 / 97 9 Hydrocarbons containing only single bonds between the carbon atoms are called. A B C D E alkenes alkynes aromatics alkanes ketones

26 Slide 26 / The general formula of an alkane is. A C 2n H 2n+2 B C n H 2n C C n H 2n+2 D C n H 2n-2 E C n H n

27 Slide 27 / Which is the formula of an alkane? A C 10 H 10 B C 10 H 18 C C 10 H 20 D C 10 H 22 E C 10 H 24

28 Slide 28 / The molecular geometry of each carbon aton in an alkane is. A B C D E octahedral sqaure planar trigonal planar tetrahedral trigonal pyramidal

29 Slide 29 / Hydrocarbons containing carbon-carbon triple bonds are called. A B C D E alkenes alkynes aromatics alkanes ketones

30 Slide 30 / Which is the formula of an alkyne? A C 10 H 10 B C 10 H 18 C C 10 H 20 D C 10 H 22 E C 10 H 24

31 Slide 31 / An alkene has at least one and has the general formula. A C-C single bond, C n H 2n+2 B C C-C double bond, C n H 2n C-C triple bond, C n H 2n D C-C double bond, C n H 2n-2 E C-C triple bond, C n H 2n-2

32 Slide 32 / could be the formula of an alkene. A C 3 H 8 B C 3 H 6 C C 6 H 6 D C 17 H 36 E CH 8

33 Slide 33 / Which of the following hydrocarbons has a double bond in its carbon skeleton? A C 3 H 8 B C 2 H 6 C CH 4 D C 2 H 4 E C 2 H 2

34 Slide 34 / The compound below is an. A B C D E alkyne alkene alkane aromatic compound olefin

35 Slide 35 / The gasoline consumed by an automobile is a fossil fuel consisting mostly of A B C D E aldehydes amino acidd alcohols hydrocarbons thiols

36 Slide 36 / 97 Isomers Hydrocarbons exhibit a phenomenon called isomerism- existence of different molecular arrangement but same formula Isomers are compounds with the same molecular formula but different structures and properties. There are 3 different types of isomers: Structural isomers Geometric isomers click here for an animation on Isomers Enantiomers

37 Slide 37 / 97 Structural Isomers Structural isomers have different covalent arrangements of their atoms. These three compounds all have the same molecular formula, but differ in which atoms are bonded together.

38 Slide 38 / 97 Geometric Isomers Geometric isomers must contain a C=C double bond. Geometric isomers have the same covalent arrangements but differ in spatial arrangements. Geometric isomers are referred to as either cis or trans. cis isomer The two CH 3 groups are on the same side. trans isomer: The two CH 3 groups are on opposite sides.

39 Slide 39 / 97 Enantiomers Enantiomers are isomers that are mirror images of each other. Enantiomers cannot be superimposed on each other. Enantiomers differ in spatial arrangement around an asymmetric carbon, resulting in molecules that are mirror images, like left and right hands. The two isomers are designated the L and D isomers from the Latin for left and right (levo and dextro).

40 Slide 40 / Structural isomers are molecules that: A B C D E are enantiomers. are hydrocarbons. have a ring structure. are mirror images. differ in the covalent arrangements of their atoms.

41 Slide 41 / The two molecules shown are best described as A B C D E optical isomers radioactive isotopes structural isomers nonradioactive isotopes geometric isomers

42 Slide 42 / Which of the following is true of geometric isomers? A B C D E They have variations in arrangement around a double bond. They have an asymmetric carbon that makes them mirror images. They have the same chemical properties. They have different molecular formulas. Their atoms and bonds are arranged in different sequences

43 Slide 43 / 97 Functional groups A functional group is an atom or group of atoms that imparts special physical and chemical properties to the compound Based on the functional group, the compounds are classified as follows. Haloalkanes/alkenes/alkynes Alcohols Acids Amines Ketones Aldehydes Esters Ether

44 Slide 44 / 97 Halo- alkanes/alkenes/alkynes Haloalkanes, haloalkenes, and haloalkynes are characterized by the presence of a halogen atom (F, Cl, Br or I), in place of a hydrogen atom. CH 3 Cl, CH 2 Cl 2, CHCl 3, CCl 4, CBr 4, F 2 C=CF 2, FC = CF They are formed when one or more H atoms are replaced by halogen atom/s.

45 Slide 45 / 97 Alcohols Alcohols contain the functional group -OH (hydroxyl group). For example, in CH 4, one H is replaced by -OH The name ends with -ol, drop the alkane "e" add "ol", So, methane becomes methyl alcohol or methanol, CH 3 OH. CH 3 CH 2 OH is called ethyl alcohol or ethanol. Thiols contain the functional group -SH, (sulfhydryl group)

46 Slide 46 / 97 Naming Alcohols Alkane formula Alkane name Alcohol formula Alcohol name CH 4 methane CH 3 OH methanol C 2 H 6 ethane C 2 H 5 OH ethanol C 3 H 8 propane C 3 H 7 OH propanol C 4 H 10 butane C 4 H 9 OH butanol

47 Slide 47 / Which of the following statements is true concerning a compound that contains a hydroxyl group? A B C D E It lacks an asymmetric carbon, and it is probably a fat or lipid. It should dissolve in water. It should dissolve in a nonpolar solvent. It won't form hydrogen bonds with water. It is hydrophobic.

48 Slide 48 / In which of the structures are the atoms bonded ionic bonds? A B C D E A B C C, D, E None of the structures

49 Slide 49 / 97 Carboxylic acids The functional group is -COOH Replace one H atom in the alkane by a -COOH group HCOOH = Methanoic acid or formic acid CH 3 COOH = Ethanoic acid or acetic acid or vinegar CH 3 CH 2 COOH = Propanoic acid Drop the "e" from the parent alkane and add "oic acid" C C C OH

50 Slide 50 / 97 Amines The functional group is - NH 2 CH 3 NH 2, replace one H by an -NH 2 group CH 3 NH 2 Amino methane or Methyl amine More than one functional groups, same or different are common in organic compounds example: amino acids. They have amine and acid groups

51 Slide 51 / Which of the structures contain(s) a carboxyl group? A B C D E A B C C & E None of the structures

52 Slide 52 / What is the name of the functional group shown in the following figure? A B C D E carbonyl ketone aldehyde carboxyl hydroxyl

53 Slide 53 / A B C D E Which two functional groups are always found in amino acids? ketone and aldehyde carbonyl and carboxyl carboxyl and amino phosphate and sulfhydryl hydroxyl and aldehyde

54 Slide 54 / 97 Ketones The functional group is -C=O or "carbonyl" group Usually sandwiched between two carbon groups CH 3 CH 2 CH 3 = propane CH 3 CO CH 3 propanone or acetone ( nail polish remover) Drop e and add none CH 3 COC 2 H 5 Ethyl methyl ketone or butanone O H 3 C- C- CH 3

55 Slide 55 / 97 Ketones A function the functional group can make! Estrogen- has two hydroxyl groups in it. Testosterone - one hydroxyl group is replaced by a ketone.

56 Slide 56 / 97 Aldehydes The functional group is -CHO with a C=O bond drop 'e' of the parent alkane and add 'nal' HCHO - (1 carbon) Methanal or Formaldehyde CH 3 CHO- (2 carbon) Ethanal or Acetaldehyde

57 Slide 57 / 97 Aldehydes, Ketones and Acids The way the carbonyl group is bonded to the main body of the molecule is different in acids, ketones and aldehydes The C=O is between two other carbon atoms ( alkyl groups) in the molecule The C=O group is at the end ( terminal carbon) of the molecule and should be connected to a H atom The C=O bond should be connected to an OH group

58 Slide 58 / What is the name of the functional group shown in the following figure? (R = any carbon group) R-C=O R A B C D E carbonyl ketone aldehyde carboxyl hydroxyl

59 Ester Slide 59 / 97 The functional group is -COOR where R could be another alkyl group. Esters are formed by the combination of an acid and an alcohol by eliminating one molecule of water. They are usually pleasant smelling compounds ( natural oils and essence) CH 3 COOH + CH 3 OH --> CH 3 COOCH 3 CH 3 COOCH 3 CH 3 COOC 2 H 5 methyl acetate ethyl acetate C 2 H 5 COOCH 3 methyl propanoate

60 Slide 60 / 97 Ether The functional group is an O atom sandwiched between two carbon groups CH 3 -O- CH 3 dimethyl ether They are highly flammable and used as solvents in organic synthesis

61 Slide 61 / 97 Groups with a Carbon Oxygen Double Bond (Carbonyl Groups)

62 Slide 62 / 97 Amides Amides are formed by the reaction of carboxylic acids with amines. RCOOH + H 2 NR' --> -H 2 O CONH linkage is known as the amide linkage ( peptide) in proteins This linkage is formed when several amino acids join with their acid and amino groups together.

63 Slide 63 / Which is the best description of a carbonyl group? A B an oxygen joined to a carbon by a single covalent bond a nitrogen and two hydrogens joined to a carbon by covalent bonds C D E a carbon joined to two hydrogens by single covalent bonds a sulfur and a hydrogen joined to a carbon by covalent bonds a carbon atom joined to an oxygen by a double covalent bond

64 Slide 64 / What is the name of the functional group shown below. A B C D E carbonyl ketone aldehyde carboxyl hydroxyl

65 Slide 65 / Which of the following contains nitrogen in addition to carbon, oxygen, and hydrogen? A B C D E an alcohol such as ethanol a monosaccharide such as glucose a steroid such as testosterone an amino acid such as glycine a hydrocarbon such as benzene

66 Slide 66 / What type of functional group is shown in the compound below? A B C D E carbonyl ketone aldehyde carboxyl hydroxyl

67 Slide 67 / Which molecule contains an amine functional group?

68 Slide 68 / Which molecule contains an aldehyde functional group?

69 Slide 69 / Which molecule contains an alcohol functional group?

70 Slide 70 / Which one of the following is not an alcohol? A B C D E acetone glycerol ethanol cholesterol ethylene glycol

71 Slide 71 / 97 Macromolecules Macromolecules are large molecules composed of smaller molecules. They are complex in their structures. Carbon has the unique property of joining together via covalent bonding to form large (macro) molecules. Most macromolecules are polymers, built from monomers.

72 Slide 72 / 97 Macromolecules Three of the classes of life s organic molecules are polymers: Proteins Carbohydrates Nucleic acids There are some macromolecules that are not polymers: lipids phospholipids steroids

73 Slide 73 / 97 Polymers Although organisms share the same limited number of monomer types, each organism is unique based on the arrangement of monomers into polymers An immense variety of polymers can be built from a small set of monomers Polymer Proteins Carbohydrates Nucleic acids Made of these monomers Amino acids Simple sugars (monosaccharides) Nucleotides

74 Slide 74 / 97 Polymers Is a long molecule consisting of many similar building blocks called monomers Monomers form larger molecules by condensation reactions called dehydration reactions short polymer Monomer longer polymer

75 Slide 75 / 97 Amino Acids and Proteins Proteins are formed when several amino acids combine together Acid and amine end of the molecules join together to form long peptide chain Peptide chain with 50 or more amino acids can form an individual protein.

76 Slide 76 / 97 Carbohydrates (sugars) Simple sugars are poly-hydroxy aldehydes or ketones. Table sugar, (sucrose) is made up of glucose and fructose. They all have several hydroxyl groups in their structure that makes them soluble in water. C Glucose and fructose are monosaccharides. Sucrose is a disaccharide. glucose (monosaccharide) fructose

77 Slide 77 / 97 Carbohydrates (sugars) In solution, they form cyclic structures. These can form chains of sugars that form structural molecules such as starch and cellulose.

78 Slide 78 / 97 Nucleic Acids Nucleic acids are made up of monomer units called nucleotides Sugar + Base + PO 4 3- = nucleotide

79 Slide 79 / 97 Nucleic Acids Two of the building blocks of RNA and DNA are sugars (ribose or deoxyribose) and cyclic bases (adenine, guanine, cytosine, and thymine or uracil)

80 Slide 80 / 97 Acid Sugar Bases RNA Ribonucleic acid ribose A, C, G and U DNA Deoxyribonucleic acid deoxyribose A, C, G and T Function make proteins carry genetic code

81 Slide 81 / 97 Nucleic Acids Nucleotides combine to form the familiar double-helix form of the nucleic acids The blue ribbon is the sugar/ phosphate backbone The bases are the rungs in the (spiral) ladder The nucleotides join together via hydrogen bonding through their bases A-T, C-G etc.

82 Slide 82 / Which of the following is not one of the four major groups of macromolecules found in living organisms? A B C D E glucose carbohydrates lipids proteins nucleic acids

83 Slide 83 / Glucose is a type of. A B C D E amino acid protein carbohydrate nucleotide nucleic acids

84 Slide 84 / Nucleic acids are made up of. A B C D E amino acids proteins carbohydrates nucleotides sugars

85 Slide 85 / A nucleotide consists of. A B C glucose + fructose + amino acid glucose + fructose + phosphate group amino acid + protein + phosphate group D sugar + base + amino acid E sugar + base + phosphate group

86 Slide 86 / Polymers of polysaccharides and proteins are all synthesized from monomers by which process? A B C D E connecting monosaccharides together (condensation reactions) the addition of water to each monomer (hydrolysis) the removal of water (dehydration reactions) ionic bonding of the monomers the formation of disulfide bridges between monomers

87 Slide 87 / 97 Other complex molecules of life Fats and Lipids Are a diverse group of hydrophobic molecules Are the one class of large biological molecules that do not consist of polymers Share the common trait of being hydrophobic

88 Slide 88 / 97 Fats and Fatty Acids Fats Are constructed from two types of smaller molecules, a single glycerol and usually three fatty acids Fatty acids Carboxylic acids with a very long chain of carbon atoms. Vary in the length and number and locations of double bonds they contain CH 2 OH CH 2 OH CH 2 OH glycerol a fatty acid

89 Slide 89 / 97 Dehydration Synthesis The attachment of a fatty acid to glycerol results in a removal of a water molecule.

90 Slide 90 / 97 The diagram shows three fatty acids added to glycerol producing a fat molecule.

91 Slide 91 / 97 Saturated and Unsaturated Fatty Acids Unsaturated fatty acids Have one or more double bonds When hydrogenated ( add more Hydrogen) they become solid and saturated Mainly plant origin Saturated fatty acids Have the maximum number of hydrogen atoms possible Have no double bonds in their carbon chain Mainly animal origin

92 Slide 92 / 97 Phospholipids Have only two fatty acids Have a phosphate group instead of a third fatty acid Results in a bilayer arrangement found in cell membranes

93 Slide 93 / 97 Steroids Are lipids characterized by a carbon skeleton consisting of three or more fused rings cholesterol

94 Slide 94 / Which of the following is (are) true for the class of large biological molecules known as lipids? A B C D E They are insoluble in water. They are an important constituent of cell membranes. They provide the least amount of energy in living organisms Only A and B are correct. A, B, and C are correct.

95 Slide 95 / Saturated fatty acids A are the predominant fatty acid in corn oil. B C D E have double bonds between carbon atoms of the fatty acids. have a higher ratio of hydrogen to carbon than do unsaturated fatty acids. are usually liquid at room temperature. are usually produced by plants.

96 Slide 96 / The hydrogenation of vegetable oil would result in which of the following? A B C D E a decrease in the number of carbon-carbon double bonds in the oil (fat) molecules an increase in the number of hydrogen atoms in the oil (fat) molecule the oil (fat) being a solid at room temperature A and C only A, B, and C

97 Slide 97 / 97