Does Hexane and Hex-1-ene dissolve in Bromine Water?

Question

When you add hexane and hex-1-ene to bromine water, how do you know it doesn't dissolve? Colour?

Also, how do you know that acids, bases and alcohols (ethanol), dissolve in water? Physical evidence?

And why doesn't alcohol change litmus paper?

Thanks

Answer 1

Hexane does not react with bromine under these conditions - as it is a saturated hydrocarbon - so theres no colour change. And no, it won't dissolve either. The forces of attraction between the hexane molecules and between the water molecules are stronger than those between hexane and water... so they don't mix. As a very loose guide, "like dissolves like".



Hex-1-ene will react with aqueous bromine to give a colourless 1-bromohexan-2-ol (NOT bromohexane as suggested by other answerer), so there is a colour change from red/brown to colourless.



Alcohols in water don't change the colour of litmus paper (or other indicators) because they are neutral.

Answer 2

Hex-1-ene would undergo hydrohalogenation to become bromohexane.

Whether there are any outward signs of it, I don't know.



CH2=CH2-CH2-CH2-CH2-CH3 + Br ------->



...H..Br

H-C-C-CH2-CH2-CH2-CH3 2-bromohexane

...H..H

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Answer 3

Hex-a million-ene could submit to hydrohalogenation to become bromohexane. whether there are any outward symptoms of it, i don't understand. CH2=CH2-CH2-CH2-CH2-CH3 + Br -------> ...H..Br H-C-C-CH2-CH2-CH2-CH3 2-bromohexane ...H..H Zaitzev product