[defencegrid]

I put some xylene in a test tube and added two drops of Potassium Permanganate and one drop of 1M Sulphuric Acid.  I was expecting the colour to disappear, but the colour did not change. 

As far as I know Xylene is an alkene, so why did the colour remain?

[AWK]

As far as I know Xylene is an alkene

Are you sure this statement is true?

[defencegrid]

As far as I know Xylene is an alkene

Are you sure this statement is true?

Well Wikipedia says that Xylene is dimethylbenzene, so I guess being an aromatic compound Potassium Permanaganate cannot break the the double bonds.

[kriggy]

actualy it can oxidize the methyls to COOH or it can oxidize the ring itself (for example, adipic acid is produced by oxidazion of benzene, terepthalic acid by oxidation of napthalene) but it requires elevated temperature

[AWK]

actualy it can oxidize the methyls to COOH or it can oxidize the ring itself (for example, adipic acid is produced by oxidazion of benzene, terepthalic acid by oxidation of napthalene) but it requires elevated temperature

I synthesized adipic acid by oxidation of cyclohexanone, and terepthalic acid from p-xylene (though isomerization of alkali metal pthalates to terepthalates is used in industry)

[Arkcon]

Well Wikipedia says that Xylene is dimethylbenzene, so I guess being an aromatic compound Potassium Permanaganate cannot break the the double bonds.

While you're there, do look up carefully the chemistry of aromatics, they are not simply double bonds.

[defencegrid]

Well Wikipedia says that Xylene is dimethylbenzene, so I guess being an aromatic compound Potassium Permanaganate cannot break the the double bonds.

While you're there, do look up carefully the chemistry of aromatics, they are not simply double bonds.

Yeah, the double bonds rotate around the ring.

[Borek]

Yeah, the double bonds rotate around the ring.

They definitely do not "rotate". I guess you mean there are several resonance structures in which double bonds move around the ring - but even that is just an outdated model.