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CHEM103: Organic Chemistry I

Unit 3: Alkanes   We will now transition into looking at each family of organic molecules, noting their respective properties and reactivity.  All units covering functional groups are structured into two main parts: 1) Nomenclature, Structural, and Physical Properties; and 2) Reactivity.  In the first section, we will study molecular nomenclature, or the systematic naming of molecules as defined by the International Union of Pure and Applied Chemistry (IUPAC).  In many ways, organic chemistry is analogous to learning a foreign language.  We must learn how to describe structures in the language that organic chemists use.

We will start with the simplest hydrocarbons: the alkanes.  Alkanes are hydrocarbons with only carbon and hydrogens.  In addition to nomenclature and properties, this unit will cover the concept of isomerism in detail.  Isomerism is the study of many different structures that molecules with same chemical formula can have.  The unit will conclude with a section on the reactivity of alkanes.  Alkanes are often described as non-reactive, inert, or low-reactive compounds.  However, under drastic conditions, these molecules can react and yield many of the molecules and materials we encounter in our daily life, including the major components in gasoline.

Unit 3 Time Advisory
This unit will take you 27.5 hours to complete.

☐    Subunit 3.1: 7.5 hours

☐    Subunit 3.2: 5.5 hours

☐    Sub-subunit: 3.2.1: 1.5 hours

☐    Sub-subunit: 3.2.2: 1.5 hours 

☐    Sub-subunit: 3.2.3: 2 hours    

☐    Subunit 3.3: 5.5 hours

☐    Subunit 3.4: 4 hours

☐    Subunit 3.5: 5 hours

☐    Sub-subunit 3.5.1: 2 hours

☐    Sub-subunit 3.5.2: 3 hours

Unit3 Learning Outcomes
Upon successful completion of this unit, the student will be able to:

  • Derive the name of alkanes from their molecular structure and vice versa. 
  • Draw stereoisomers using Newman projections.
  • Give details on the energetics of stereoisomers of linear alkanes.
  • Draw and give details of the conformational isomers of cycloalkanes.
  • Describe typical reactions involving alkanes such as combustion and halogenation.

3.1 Nomenclature of Alkanes and Cycloalkanes   - Web Media: Khan Academy: Salman Khan’s “Naming Simple Alkanes”; Naming Alkanes with Alkyl Groups”; “Correction – 2-Propylheptane should never be the name!”; “Common and Systematic Naming – Iso, Sec, and Tert Prefixes”; “Organic Chemistry Naming Examples 1”; “Organic Chemistry Naming Examples 2”; “Organic Chemistry Naming Examples 3”; “Organic Chemistry Naming Examples 4”; “Organic Chemistry Naming Examples 5 Link: Khan Academy: Salman Khan’s “Naming Simple Alkanes” (HTML); "Naming Alkanes with Alkyl Groups” (HTML); “Correction – 2-Propylheptane should never be the name!” (HTML); “Common and Systematic Naming – Iso, Sec, and Tert Prefixes” (HTML); “Organic Chemistry Naming Examples 1 (HTML); “Organic Chemistry Naming Examples 2” (HTML); “Organic Chemistry Naming Examples 3” (HTML); “Organic Chemistry Naming Examples 4 (HTML); “Organic Chemistry Naming Examples 5” (HTML)
 
Instructions: Please watch the nine videos to reinforce the reading material (82:28 minutes).  Several examples are worked to help familiarize you with the naming methods.

 Terms of Use: These resources are licensed under a [Creative
Commons Attribution-NonCommercial-NoDerivs 3.0 Unported
License](http://creativecommons.org/licenses/by-nc-nd/3.0/). They
are attributed to the Khan Academy.
  • Reading: Michigan State University: Department of Chemistry: Professor William Reusch’s “Nomenclature” Link: Michigan State University: Department of Chemistry: Professor William Reusch’s “Nomenclature” (HTML)
     
    Instructions: Read the sections titled “Naming Organic Compounds,” “Alkanes,” and “Cycloalkanes.”  Click on the various links on this webpage to see additional examples.  At the end of the cycloalkane section, there is a scroll down menu with link to several “Practice Problems.”  Please select the first question and do the exercises.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Lecture: YouTube: University of California, Irvine: Professor James Nowick’s “Nomenclature of Alkanes, Conformations of Ethane” Link: YouTube: University of California, Irvine: Professor James Nowick’s “Nomenclature of Alkanes, Conformations of Ethane” (YouTube)
     
    Instructions: Please watch the first 20 minutes of this lecture.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

3.2 Stereoisomers of Linear Alkanes   - Reading: University of British Columbia: Professor W. Stephen McNeil’s “Conformations of Alkanes” and Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: Stereoisomers Links: University of British Columbia: Professor W. Stephen McNeil’s “Conformations of Alkanes” (HTML) and Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Stereoisomers” (HTML)
 
Instructions: For the first link, read the sections titled “Stereoisomers,” “Conformational Isomers,” “Ethane Conformations,” and “Butane Conformations.”  Read the entirety of the Michigan State University webpage.  These resources also cover subunits 3.2.2 and 3.2.3.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Web Media: YouTube: Far From Standard Tutoring: John Hennessy’s “Newman Projections" Link: YouTube: Far From Standard Tutoring: John Hennessy’s “Newman Projections" (YouTube)
     
    Instructions: Please watch the entire video (about 8 minutes).  This resource also covers subunit 3.2.1.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

  • Lecture: YouTube: University of California, Irvine: Professor James Nowick’s “Nomenclature of Alkanes, Conformations of Ethane” Link: YouTube: University of California, Irvine: Professor James Nowick’s “Nomenclature of Alkanes, Conformations of Ethane” (YouTube)
        
    Instructions: Having already watched the first 20 minutes of this lecture in subunit 3.1, please now watch the last 30 minutes.  This resource covers the topics outlined in subunits 3.2.2 through 3.2.3.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

  • Assessment: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Distinguishing Different Formulas” and “Identifying Conformer Representations” Links: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Distinguishing Different Formulas” (HTML) and “Identifying Conformer Representations” (HTML)
     
    Instructions: Focus only on linear molecules.  Practice drawing alkanes and their stereoisomers using these interactive exercises from the Virtual Textbook of Organic Chemistry.  Please follow the directions on each webpage to complete the assessment.  This resource covers topics outlined in subunits 3.2.1 through 3.2.3.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.

3.2.1 Newman Projections   3.2.2 Conformational Isomers   - Web Media: Khan Academy: Salman Khan’s “Newman Projections” Link: Khan Academy: Salman Khan’s “Newman Projections” (HTML)
 
Instructions: Please watch the video, which demonstrates how Newman projections arise (14:22 minutes).

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-NoDerivs 3.0 Unported
License](http://creativecommons.org/licenses/by-nc-nd/3.0/). It is
attributed to the Khan Academy.

3.2.3 Examples of Ethane and Butane   - Web Media: Khan Academy: Salman Khan’s “Newman Projections 2” Link: Khan Academy: Salman Khan’s “Newman Projections 2” (HTML)
 
Instructions: Please watch the video, which demonstrates how to draw Newman projections for ethane and butane (11:12 minutes).

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-NoDerivs 3.0 Unported
License](http://creativecommons.org/licenses/by-nc-nd/3.0/). It is
attributed to the Khan Academy.

3.3 Isomers of Cycloalkanes   - Reading: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Cycloalkane Configurational Isomers,” “Ring Conformations,” “Cycloalkanes,” and “Substituted Cyclohexanes" Links: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Cycloalkane Configurational Isomers,” (HTML) “Ring Conformations,” (HTML) “Cycloalkanes,” (HTML) and “Substituted Cyclohexanes" (HTML)
 
Instructions: Read the sections linked above.  In the previous unit, we learned about the different conformations an alkane can assume upon free rotation along a carbon-carbon bond.  In cycloalkanes, this free rotation is not permitted as atoms are "locked" in a ring structure.  These rings are not as rigid as they might appear.  In fact, cycloalkanes often undergo "ring flip."  In this section, you will learn about this flipping phenomena, the stable configuration of cycloalkanes (called "chair"), the less stable one (called "boat"), and the energy barrier to be overcome for ring flipping. 
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.

3.4 Drawing Chair Conformations of Cyclohexanes   - Reading: University of California, Davis: UC Davis ChemWiki: "Ring Strain and the Structure of Cycloalkanes” Link: University of California, Davis: UC Davis ChemWiki: "Ring Strain and the Structure of Cycloalkanes." (HTML or PDF)
 
Instructions: Read the tutorial webpage, and complete the practice problems.
 
Note: You can view this as a PDF by clicking the “Make PDF” button near the top of the linked webpage.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Lecture: YouTube: UCITLTC: University of California, Irvine: Professor James Nowick’s “Conformations of Cyclohexane” Link: YouTube: UCITLTC: University of California, Irvine: Professor James Nowick’s “Conformations of Cyclohexane” (YouTube)
     
    Instructions: Please watch the video (36:58 minutes) to understand the conformations of cyclohexane. 
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

3.5 Reactivity   - Reading: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Reactions of Alkanes" Link: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Reactions of Alkanes" (HTML)
 
Instructions: Read the entire webpage about the reactivity of alkanes.  At the bottom of the page, from the Practice Problems scroll-down menu, select and complete the “Halogenations of Alkanes” problems.  This resource covers subunits 3.5.1 through 3.5.2.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Web Media: YouTube: mfmayer’s “Introduction to Halogenation of Alkanes” and YouTube: jamesmungall's Channel: James Mungall Chemistry Tutorials by James Mungall: "Radical Substitution - Chlorination of Methane” Links: YouTube: mfmayer’s “Introduction to Halogenation of Alkanes” (YouTube) and YouTube: jamesmungall's Channel: James Mungall Chemistry Tutorials by James Mungall: “Radical substitution - Chlorination of Methane” (YouTube)
     
    Instructions: Please watch these brief videos (3-5 minutes each) to understand the reactivity of alkanes.  This resource also covers subunit 3.5.2.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above. 

3.5.1 Combustion   3.5.2 Halogenation