Alkane and Alkene Reactions

Transcription

1 Name: Date: Pd: Alkane and Alkene Reactions 1. Give the structure (structural fmula and condensed structural fmula) of the maj ganic product of the following reactions. a. hexane and chline Reaction Type: Substitution of Halogens Cl (Chline can be on any carbon) b. 1-hexene and chline Reaction Type: Addition of Halogens ClCHCl c. 1-hexene and HCl gas Reaction Type: Addition of Halogen halides CHCl Cl d. 1-hexyne and excess chline Reaction Type: Addition of Halogens CHCl 2 CCl 2 e. 1-hexene and concentrated sulfuric acid Reaction Type: Hydration (OH) CH(OH)

2 f. 1-hexene and hydrogen gas in the presence of heat and a nickel catalyst Reaction Type: Hydrogenation 2. Comment on the following observations. a. Hydrocarbons have low boiling points compared to other ganic compounds of similar fmula weights. Hydrocarbons are nonpolar (only contain carbon and hydrogen). Molecules of hydrocarbons are attracted to each other only by London Dispersion Fces. They are not able to fm dipole-dipole fces hydrogen bonds. In der to boil something, the IMFs must be overcome/broken apart. London Dispersion fces are the weakest IMFs and therefe require the least amount of energy to overcome. b. Alkenes and Alkynes produce me smoke than alkanes during combustion. Alkenes, Alkynes, and Arenes undergo me incomplete combustion due to the presence of the C=C bonds. Incomplete combustion produces soot (unburned carbon). As the C:H ratio increases with unsaturation, there is an increase in incomplete combustion and smokiness. c. Treatment of an alkane with chline requires UV radiation to cause reaction, whereas an alkene will react instantly with chline. The C=C double bond is me reactive than the C-C single bond so UV radiation is not required to start the reaction. d. The product of the reaction of an alkane with chline is unpredictable. The radical chline can attack any of the C-H bonds on an alkane so the chline could end up substituting any H on the carbon chain. 3. Draw the products expected from the following reactions and name the reactant and product a. + HBr propene + hydrobromic acid 2-bromopropane 1-bromopropane

3 b. 2-methylbut-2-ene and water in the presence of concentrated sulfuric acid 2-methylbutan-1-ol 2-methylbutan-2-ol c. 3,4-dimethylpent-2-ene + Hydrochlic acid + HCl 2-chlo-3,4-dimethylpentane 3-chlo-3,4-dimethylpentane

4 d. 3- methylbut-1-ene and concentrated sulfuric acid + H 2 SO 4 3-methylbutan-2-ol 3-methylbutan-1-ol e. ethane and bromine gas bromoethane f. 1-butyne + 1 equivalence of HBr +HBr g. 1-butyne + 2 equivalence of HBr 1,2-dibromobutane 2,2- dibromobutane +HBr 1,1- dibromobutane

5 h. butane 4. F the following reactions, provide the reagent necessary to effect the transfmation. a. +HBr b. concentrated H 2 SO 4 (write over arrow) c. + H 2 and Nickel Catalyst (Catalyst written over arrow) d. excess Br 2 5. Show the complete mechanism f the reaction of methane with chline in the presence of UV light. Be careful to show all the crect curly arrows and to include the initiation, propagation and termination steps.

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