ORGANIClab211 - at the time. 2. Arrange the four...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Experiment No.: Experiment Name: Date: 21 Free-Radical Stability 06/30/10 Name: Course: Paul Gonzales CH 2123 Purpose: to determine the relative stabilities of reaction intermediates and measure the reactivities of substances. Procedure: 1. Add 2.0 mL of dichloromethane to each of four clean, dry, labeled 13 x 100 mm test tubes. To each test tube, add 0.5 mL of a different aromatic hydrocarbon - toluene, ethylbenzene, isopropyl benzene, or t-butylbenzene – and swirl to mix. Under the hood, carefully add 0.5 mL of freshly prepared 1.0 M bromine in dichloromethane to each test tube, then stopper and shake it. Record the time of bromine addition to the nearest minute. Set the test tubes in a well lighted location such as a windowsill, and record the approximate time it takes for each solution to become colorless. Observe the solutions closely for the first five minutes or so, and then at intervals during the lab period. If two or more solutions are not completely colorless by the end of the lab period, describe the relative intensity of their colors
Background image of page 1

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

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: at the time. 2. Arrange the four hydrocarbons in order of their reactivity toward bromine, most reactive first, and compare your results with your predictions. Write a balanced equation for each reaction and give structures for each free radical intermediate. Arrange the free radicals in order of stability and explain their relative stabilities. Write a complete mechanism for the bromination of toluene. Data and Observations: 1) Isopropyl Benzene immediately cleared 2) ethylbenzene a minute or so, yellowish 3) Toluene Several minutes light orange 4) Tertbutyl - not decolorized orange Conclusion: Our results of the most reactive begin with isopropyl benzene, continue 1 with ethylbenzene, toluene, and finally tertiary butyl. This reactivity order can be explained by these hydrocarbons reactivity with free radical bromination. The first 3 occur at the benzylic position with the more alkyl groups meaning more electron donating plausibility. 2...
View Full Document

Page1 / 2

ORGANIClab211 - at the time. 2. Arrange the four...

This preview shows document pages 1 - 2. Sign up to view the full document.

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