Photochemical Bromination of an Alkane
- Page ID
- 3022
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Chemical Concepts Demonstrated
- Light-catalyzed reactions
- Thermolytic and photolytic reactions
- Free-radical reactions
- Reactivity of alkanes
Demonstration
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Observations
The pentene changes to colorless very quickly. The pentane changes after exposure to the overhead's light.
Explanation (including important chemical equations)
The light-catalyzed reaction between an alkane and bromine can be stated as follows:
Chain initiation: Br2 + hv --> 2 Br.
Chain propogation: Br. + R-H --> R-Br + H.
H. + Br2 --> H-Br + Br.
Chain termination: 2 Br. --> Br2
2 H. --> H2
H. + Br. --> HBr
Contributors
- Dr. George Bodner (Perdue University)