chapter 12 - 1 Chapter Twelve ALKENE Alkenes Introduction s...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 Chapter Twelve ALKENE Alkenes Introduction s Unsaturated Unsaturated hydrocarbons hydrocarbons that that contain contain one or more C-C double bonds, triple bonds, or benzenes. b Alkenes: one or more double bonds. (C n H 2n ) b Alkynes: one or more triple bonds. (C n H 2n-2 ) s Thermal Thermal cracking cracking: major process for the production of ethylene. b A saturated hydrocarbon is converted to an unsaturated hydrocarbon. C H 2 CH 2 CH 3 CH 3 + H 2 thermal cracking Alkenes s Structure: b The VSEPR model predicts bond angles of 120 about each carbon of a double bond. b In ethylene, the actual angles are close to 120. b In substituted alkenes, angles about each carbon of the double bond may be greater than 120 because of repulsion between groups bonded to the double bond. H C C H H H 121.7 H 3 C C C H H H 124.7 Ethylene Propene Structures s Alkenes: under normal conditions, no rotation allowed around the carbon-carbon double bond. s Cis-Trans isomerism trans-2-Butene mp -106C, bp 1C cis-2-Butene mp -139C, bp 4C H C C CH 3 H 3 C H H C C H H 3 C CH 3 2 Nomenclature of Alkenes and Alkynes s IUPAC system s Prefix---indicate carbon number in the chain. s Suffix- ene---indicate alkene. s Suffix yne---indicate alkyne. Step 1 Step 1. Find the longest carbon chain that includes double bond (or triple bond). Step 2 Step 2. Number the chain so that double bond has the lower set of number. Designate the position of the double bond by its first C number. Step 3 Step 3. Branched alkenes are named in a manner similar to alkanes....
View Full Document

This note was uploaded on 12/18/2010 for the course CHEM 10054 taught by Professor Ding during the Spring '10 term at Kent State.

Page1 / 6

chapter 12 - 1 Chapter Twelve ALKENE Alkenes Introduction s...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online