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? 發問於 科學及數學化學 · 1 十年前

reaction between Br and cyclohexene?

1 what is the equation when adding Br into cyclohexene? what is the product?

2 why it will turn from brown to colourless?

3What is the condition? Room temperature? Any catalysis is needed?

4What is the observations? What will I see when reaction occurs? ? what will happen? Any heat?

1 個解答

  • 1 十年前

    1. The bromine will have addition reaction with the >=< bond in cyclohexene to form the 1,2-dibromocyclohexane.

    >=< + Br2 = >CBr-CBr<

    2. Since the resultant 1,2-dibromocyclohexane is colorless in color, the bromine will disappear after the reaction. So, the reaction mixture will become colorless.

    3. The cyclohexene is quite reactive towards the additin of bromine. So, teh reaction will occur even in room temperature.

    4. Whether the observatio is obvious depends on teh concentration of the bromine. If concentrated bromine solution is added, no obvious change will be since the discoloration is masked by the excessive bromine. If just trace amount of bromine is added, you will see the brown color from bromine will disappear after addition to the solution with cyclohexene. Usually, no heat will be generatd in tis reaction since the heat will be used up to evaporate the solvent even the reaction is exothermic.

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