Bromine water was decolourized by acetylene in the the last experiment, because two bromine atoms were added to one of the double bondings of ethine molecules. In the following experiment you will mix bromine water with two liquid hydrocarbons: Hexene is unsaturated like acetylene, hexane is saturated.
*Both hydrocarbons are very inflamable. *Bromine water is poisonous. *Ask for an adult. * Work outdoors.   * Use a tray.

What you need:
Two injection bottles with bromine water, dropper bottles with cyclohexane and cyclohexene, stoppers.

* Experimentleft photo:Half-fill the bottles with bromine water.
* Add 20 drops of cyclohexane to the left vial and 20 drops cyclohexene to the right one.
* Close the stoppers, shake vigorously and wait.
Observation and explanation cyclohexene right photo, right bottle)
The hydrocarbon floats on the aqueous solution. Cyclo hexene decolourizes bromine water, bromine molecules are added:                            C₆H₁₀(l) + Br₂(aq) --addition--> C₆H₁₀Br₂(l)
Observation and explanation cyclohexane right photo, left bottle)
Cyclohexane floats on the aqueous solution. The colour of bromine concentrates in the upper layer as the hydrocarbon dissolve better than in water. There is no chemical reaction.