Reactions of Hydrocarbons
Properties and Reactions of Hydrocarbons
Abstract
Introduction
Hydrocarbons are organic materials that contain only carbon and hydrogen atoms, these molecules can be saturated or unsaturated and acyclic, cyclic, or aromatic. In this experiment we used a variety of methods to examine the physical and chemical properties of hydrocarbons. The first experiment we tested a variety of solvents to see if they dissolved our alkane (Decalin). One would expect that non-polar solvents will dissolve alkanes because they are non polar as well 1. If the solvent did not dissolve in the alkane we heated the solution with a heat gun, because higher temperature increases solubility because energy in the form of heat can break bonds and allow for the molecules to join together. This is the reversed for a decrease in temperature the molecules move around less so there is less interaction between solute and solvent. We also differentiated alkanes and alkenes. Alkanes only contain c-c single bonds, are saturated, and are the least reactive. Alkenes are c=c double bonds, more reactive than alkanes, and unsaturated. In the next part of the experiment we added bromine to alkenes. This caused an electrophilic halogenation reaction. If the bromine reacted with the alkene the bromine would discolor from orange and turn clear.
Experiment
Part A) Solubility of Alkanes: 1 mL of nine solvents (water, methanol, n-butanol, ethylene, glycol, acetone, hexane, toluene, ethyl acetate, and dichloromethane.) was added to nine sample vials. Each vial then had 0.5 mL of the alkane decalin added to each one. The mixtures were stirred to determine if the materials dissolved. If the material was insoluble it was heated with an air gun to see if it would aid in dissolving the solution. This test helped us determine what kinds of solvents are useful for dissolving alkanes.
Part B) Reactivity of Alkanes and Alkenes in Sulfuric Acid: 0.5 mL of cyclohexane was added to one vial and 0.5 mL
Abstract
Introduction
Hydrocarbons are organic materials that contain only carbon and hydrogen atoms, these molecules can be saturated or unsaturated and acyclic, cyclic, or aromatic. In this experiment we used a variety of methods to examine the physical and chemical properties of hydrocarbons. The first experiment we tested a variety of solvents to see if they dissolved our alkane (Decalin). One would expect that non-polar solvents will dissolve alkanes because they are non polar as well 1. If the solvent did not dissolve in the alkane we heated the solution with a heat gun, because higher temperature increases solubility because energy in the form of heat can break bonds and allow for the molecules to join together. This is the reversed for a decrease in temperature the molecules move around less so there is less interaction between solute and solvent. We also differentiated alkanes and alkenes. Alkanes only contain c-c single bonds, are saturated, and are the least reactive. Alkenes are c=c double bonds, more reactive than alkanes, and unsaturated. In the next part of the experiment we added bromine to alkenes. This caused an electrophilic halogenation reaction. If the bromine reacted with the alkene the bromine would discolor from orange and turn clear.
Experiment
Part A) Solubility of Alkanes: 1 mL of nine solvents (water, methanol, n-butanol, ethylene, glycol, acetone, hexane, toluene, ethyl acetate, and dichloromethane.) was added to nine sample vials. Each vial then had 0.5 mL of the alkane decalin added to each one. The mixtures were stirred to determine if the materials dissolved. If the material was insoluble it was heated with an air gun to see if it would aid in dissolving the solution. This test helped us determine what kinds of solvents are useful for dissolving alkanes.
Part B) Reactivity of Alkanes and Alkenes in Sulfuric Acid: 0.5 mL of cyclohexane was added to one vial and 0.5 mL
References: [1] Setzer, M.C.; Setzer, W.N. Organic Chemistry Laboratory Manual Cengage Learning: Ohio,2004 [2] Clark Jim. (2000). Retrieved February 7, 2010, from http://www.chemguide.co.uk/mechanisms/eladd/symbr2.html [3] University of Michigan. (2010). Retrieved February 9, 2011, from http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/addene1.htm