10.1 FUNDAMENTALS OF ORGANIC CHEM
Page 1: Introduction
Topic: Organic Chemistry 10.1 Fundamentals
Author: Merinda Sautel, Alameda Int’l Jr/Sr High School, Lakewood, CO
Contact: msautel@jeffco.k12.co.us
Page 2: Essential Idea
Organic chemistry focuses on the chemistry of compounds containing carbon.
Nature of Science (1.4): Importance of serendipity in scientific discoveries (e.g., PTFE and super glue).
Nature of Science (4.5): Ethical implications of chemicals like drugs, additives, and pesticides that can harm people and the environment.
Page 3: International-Mindedness
A small number of nations control the world’s oil resources, influencing global politics.
Importance of interdependence between oil-importing and exporting countries.
Octane rating measures fuel performance, highly variable by region due to different measurement practices.
Page 4: Theory of Knowledge
The term "organic chemistry" stems from historic misconceptions about a vital force needed to explain life chemistry.
Discussion on how vocabulary can develop from misunderstandings.
Example: Kekule's dream-led inspiration for the cyclic structure of benzene; questioning the role of non-analytical knowledge in scientific discovery.
Page 5: Understanding/Key Idea 10.1.A
A homologous series is a series of compounds in the same family with the same general formula, differing by a common structural unit.
Page 6: Homologous Series
Definition: A family of organic compounds sharing common features.
Successive members differ by a –CH2 group.
Represented by the same general formula.
Show a gradation in physical properties and similar chemical properties.
Page 7: Members Differ by –CH2
Moving from one member of a homologous series to the next increases molecular mass by a fixed amount (addition of –CH2).
Example: Transition from propane to butane adds one carbon and two hydrogen atoms.
Page 8: Members Represented by Same General Formula
Alkanes: CnH2n+2; Alkenes: CnH2n.
Functional Group: A small atom group that gives characteristic properties to compounds (e.g., Alcohols: CnH2n+1OH or ROH).
Page 9: Members Show Gradation of Physical Properties
Physical properties (boiling point, density, viscosity) vary predictably as the chain length changes due to the addition of –CH2 groups.
Page 10: Members Show Similar Chemical Properties
Same functional groups imply similar reactivity; predicting properties based on characteristic reactions of functional groups is possible.
Page 11: Application/Skills
Be prepared to explain boiling point trends within homologous series.
Page 12: Boiling Point Trends
Boiling point increases with longer carbon chains due to stronger van der Waals forces.
Page 13: Boiling Points of Alkanes
First four alkanes: gas at room temperature.
Next four: liquid.
Notable boiling points: Methane (-164°C) to Octane (125°C).
Page 14: Application/Skills
Distinguish between empirical, molecular, and structural formulas.
Page 15: Empirical Formula
Definition: Simplest whole number ratio of atoms in a compound.
Derived from combustion analysis but does not provide actual atom counts.
Page 16: Molecular Formula
Definition: Actual number of each element's atoms, a multiple of the empirical formula.
Does not indicate the arrangement of atoms; thus, limited in value.
Page 17: Understanding/Key Idea 10.1.B
Structural formulas can be presented in full and condensed formats.
Page 18: Structural Formula
Full structural formulas must depict every bond and atom.
Must show all C's, H's, and functional groups for full credit. Skeletal structures are rejected.
Page 19: Condensed Structural Formula
Simplified structural formula that omits assumed bonds and groups atoms.
Page 20: Stereochemical Formula
Attempts to depict three-dimensional atomic positions.
Uses solid wedge for bonds in front of the page and dotted line for those at the back.
Page 21: Understanding/Key Idea 10.1.C
Saturated Compounds: Contain only single bonds.
Unsaturated Compounds: Contain double or triple bonds.
Page 22: Guidance
Apply IUPAC rules for naming:
Non-cyclic alkanes and halogenoalkanes (up to halohexanes).
Alkenes (up to hexene).
Alkynes (up to hexyne).
Page 23: Guidance
Compounds with up to 6 carbon atoms with one functional group: alcohols, ethers, aldehydes, halogenoalkanes, ketones, esters, carboxylic acids, amines, amides, nitriles, arenes.
Page 24: Nomenclature: IUPAC System
IUPAC provides a systematic naming process based on molecule size and functional groups.
Page 25: Rule 1: Identify Longest Straight Chain
Longest carbon chain is the “stem.” Memorize:
Meth: 1, Eth: 2, Prop: 3, But: 4, Pent: 5, Hex: 6, Hept: 7, Oct: 8, Non: 9, Dec: 10.
Page 26: Rule 2: Identify Functional Group
Functional groups impart specific suffixes, replacing –ane in parent alkanes.
Page 27: Understanding/Key Idea 10.1.D
Functional groups are the reactive parts of molecules.
Page 28: Guidance
Differentiate between class names and functional group names (e.g., -OH: functional group hydroxyl; class name alcohol).
Page 29: Functional Group: C-C (Alkanes)
Alkanes:
Suffix: –ane (saturated hydrocarbons).
General formula: CnH2n+2.
Class: alkane; Functional group: none.
Page 30: Functional Group: C=C (Alkenes)
Alkenes:
Suffix: –ene (unsaturated).
Named by the smallest numbered carbon in the double bond (e.g., but-1-ene).
General formula: CnH2n.
Page 31: Functional Group: C≡C (Alkynes)
Alkynes:
Suffix: –yne (unsaturated).
Named by the smallest numbered carbon in the triple bond (e.g., but-1-yne).
General formula: CnH2n-2.
Page 32: Functional Group: -OH (Alcohols)
Alcohols:
Suffix: –anol.
Named with position of functional group (e.g., propan-2-ol).
General formula: CnH2n+1OH.
Page 33: Functional Group: R-O-R’ (Ethers)
Ethers:
Suffix: –oxyalkane.
General formula: R-O-R’.
Page 34: Functional Group: -C=O (Aldehydes)
Aldehydes:
Suffix: –anal.
Named with carbon counting (e.g., propanal).
General formula: R-CHO.
Page 35: Functional Group: R-C=O-R’ (Ketones)
Ketones:
Suffix: –anone.
General formula: R-CO-R’.
Page 36: Functional Group: -C=O, O-H (Carboxylic Acids)
Carboxylic Acids:
Suffix: –anoic acid.
General formula: CnH2n+1COOH.
Page 37: Functional Group: -C=O, O-R (Esters)
Esters:
Suffix: –anoate.
General formula: R-COO-R’.
Page 38: Functional Group: -NH2 (Amines)
Amines:
Suffix: –anamine.
Page 39: Primary, Secondary, Tertiary Amines
Primary: One –NH2 group.
Secondary: One alkyl group bonded to nitrogen.
Example: N-methylpropanamine.
Tertiary: Two alkyl groups bonded to nitrogen.
Page 40: Functional Group: -C=O, N-H (Amides)
Amides:
Suffix: –anamide.
Page 41: Primary, Secondary, Tertiary Amides
Primary: One –NH2 group.
Secondary: One alkyl group bonded to nitrogen.
Tertiary: Two alkyl groups bonded to nitrogen.
Page 42: Functional Group: C≡N (Nitriles)
Nitriles:
Suffix: –anenitrile.
Page 43: Functional Group: Arenes (Aromatic Compounds)
Arenes contain the benzene ring.
Page 44: Understanding/Key Idea 10.1.E
Benzene is an aromatic, unsaturated hydrocarbon.
Page 45: Application/Skills
Discuss the structure of benzene using physical and chemical evidence.
Page 46: Structure of Benzene
Benzene has alternating double bonds between three pairs of carbon atoms.
Page 47: Historical Model of Benzene
Kekule's model (1865) proposed cyclic arrangement; explained some properties but not low reactivity.
Page 48: Advances in Benzene Structure
Current model developed with advanced technology; formula C6H6.
Page 49: Structure Geometry of Benzene
Each carbon in benzene is sp2 hybridized, forming sigma bonds at 120° angles.
Page 50: Benzene's Delocalized Pi Electron Cloud
P orbitals on carbon overlap, creating a stable, delocalized pi electron cloud.
Page 51: Bonding in Benzene
All carbon bonds are equal.
Page 52: Stability of Benzene Structure
More stable than Kekule structure by about 152 kJ/mol.
Page 53: Rule 3: Identify Substituent Groups
Substituents are named as prefixes or suffixes based on their number and type.
Page 54: Naming Multiple Substituents
Prefixes like di-, tri-, etc., are utilized when multiple identical substituents are present.
Page 55: Understanding/Key Idea 10.1.F
Structural Isomers: Same molecular formula but different atom arrangements.
Page 56: Traits of Structural Isomers
Unique chemical/physical properties; count of isomers increases with molecular complexity.
Page 57: Application/Skills
Use IUPAC rules to name straight-chain and branched isomers.
Page 58: Isomer Count Examples
Butane (C4H10): 2 isomers.
Pentane (C5H12): 3 isomers.
Hexane (C6H14): 5 isomers.
Page 59: Isomer Drawing Practice
Draw and name isomers for butane, pentane, and hexane.
Page 60: Isomers of Alkenes and Alkynes
Butene, pentene, and hexene has multiple isomer options.
Page 61: Isomer Drawing Practice for Alkenes
Practice drawing and naming isomers for butene, pentene, and hexene.
Page 62: Isomers of Alkynes
Butyne, pentyne, and hexyne also have multiple isomer options.
Page 63: Isomer Drawing Practice for Alkynes
Practice drawing and naming isomers for butyne, pentyne, and hexyne.
Page 64: Application/Skills
Identify primary, secondary, and tertiary carbon atoms in various compounds.
Page 65: Classes of Compounds
Definitions for primary, secondary, and tertiary carbon atoms and their characteristics.
Page 66: Examples of Carbon Classifications
Identifying primary, secondary, and tertiary alcohols with examples.
Page 67: Trends in Physical Properties
Discuss volatility and solubility of compounds with various functional groups.
Page 68: Influence of Structure on Properties
Both hydrocarbon skeleton and functional group impact physical properties.
Page 69: Volatility
Measure of how easily substances vaporize; related to intermolecular forces.
Page 70: Factors Affecting Volatility
Length of carbon chains and branching influence boiling points and volatility.
Page 71: Comparison of Volatility
Comparing ethanol and propane highlights the effects of hydrogen bonding on volatility.
Page 72: Summary of Volatility
Ranking of various compounds based on volatility and boiling point trends.
Page 73: Solubility in Water
Solubility is linked to ability to form hydrogen bonds with water.
Page 74: Hydrocarbon Influence
Non-polar hydrocarbon skeleton reduces solubility in water.
Page 75: Functional Group Influence on Solubility
Alcohols, carboxylic acids, and amines: soluble; others less so.
Page 76: Citations
References to textbooks and resources that contribute to the presentation material.
Key Ideas Summary of Organic Chemistry 10.1 Fundamentals
Essential Idea
Focuses on compounds containing carbon.
Importance of serendipity in scientific discoveries and ethical implications of chemicals affecting health and the environment.
International-Mindedness
Oil resource control by a few nations influences global politics; interdependence exists between oil-importing and exporting countries.
Theory of Knowledge
Organic chemistry term originates from misconceptions; vocabulary evolves from misunderstandings.
Understanding/Key Idea 10.1.A
Homologous series: compounds in the same family with the same general formula, differing by a common structural unit.
Understanding/Key Idea 10.1.B
Structural formulas can be presented in full and condensed formats, with clear differentiation required for functional groups.
Understanding/Key Idea 10.1.C
Distinction between saturated (only single bonds) and unsaturated compounds (double or triple bonds).
Understanding/Key Idea 10.1.D
Functional groups are the reactive parts of molecules; understanding their classification is essential.
Understanding/Key Idea 10.1.E
Benzene is an aromatic hydrocarbon with a stable structure different from historical models.
Understanding/Key Idea 10.1.F
Structural isomers share the same molecular formula but differ in atom arrangements, leading to unique chemical and physical properties.