Edexcel - Chemistry Unit 2 - 4 June 2013

do we need to be able to test for halogenoalkanes?

but for example do tertiary halogenoalkanes always react the fastest with water when doing an sn1 reaction? and then primary always the fastest when doing an sn2?

You wouldn't set out to do a "Sn1 reaction". The reaction would go by the mechanism with the lowest energy. So tertiary is always the fastest.

You might be asked to distinguist between an alcohol and haloalkane, but thats fairly simple.. You may also be asked to identify a halide.

do we need to be able to test for halogenoalkanes?

sorry how would i distinguish between an alcohol and a halogenoalkane?

You wouldn't be expected to draw it, but you could be asked about it! (like multiple choice question)

does anyone know what it means by this in the syallbus: demonstrate an understanding of why it is helpful to classify reagents (in the mechanisms part!)

does anyone know what it means by this in the syallbus: demonstrate an understanding of why it is helpful to classify reagents (in the mechanisms part!)

Silver nitrate solution does mean with water, yes. Probably better to say aqueous silver nitrate though.

Guys for the testing for Halogenoalkanes, some books just say add Silver Nitrate solution, whilst others say add Sodium Hydroxide/Water and THEN Silver Nitrate solution. I personally think you'd have to add the Sodium Hydroxide first, to liberate the Halide ion which would then react with the Silver Ions, BUT does silver nitrate in 'solution' means it has Water, so you can just say Silver nitrate solution?

Make sure you understand what you've written there, the first "part", where you add the NaOH (in water) to the haloalkane is just converting it to an alcohol. As a consequence you are also liberating the halide ion which you can then test with the aqueous silver nitrate solution.

Reading my textbook on preparation of 1-bromobutane from butan-1-ol. Apparently you purify the impure product with HCl to remove unreacted butan-1-ol. How does this help purify it? Doesn't it just make 1-chlorobutane? Confused :s

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