Chemical Forums

Chemistry Forums for Students => High School Chemistry Forum => Topic started by: HongKongALevelboy on September 22, 2004, 09:43:23 AM

Title: question
Post by: HongKongALevelboy on September 22, 2004, 09:43:23 AM

Below is a question from 2004 Nong Kong Advanced Level examination , i hope someone can give me a correct answer
( with the help of chemical equation , suggest why household bleach should not be usedtogether with nail vanish remover which contains propanone )

Title: Re:question
Post by: Demotivator on September 22, 2004, 10:37:24 AM

bleach (NaOCl) reacts with propanone to produce chloroform
CH3COCH3 + 6NaOCl -> CHCl3 + CH3COONa + 2 NaOH + 3 NaCl
It happens with any ketone containing a a simple methyl group: CH3COR

Title: Re:question
Post by: Donaldson Tan on September 23, 2004, 12:34:26 AM

oooo.. so chlorination occurs instead of nucleophilic addition. I thought ClO^- would add as a nucleophile.. but I didnt realise bleach is as good as chlorine water.. LOL..

Title: Re:question
Post by: AWK on September 23, 2004, 03:35:54 AM

Thjs reaction is called - haloform reaction.
For mechanism, see, eg: http://www.mhhe.com/physsci/chemistry/carey5e/Ch18/ch18-3-2b.html