IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Sciences => Topic started by: superduper2009 on May 20, 2010, 12:36:33 am

Title: Chemistry Practicals Organic Part
Post by: superduper2009 on May 20, 2010, 12:36:33 am

Hi...
guyz i just wanted to ask that what are the things that we are required to know in practicals regarding organic chemistry
i.e. the different reactions etc.

Title: Re: Chemistry Practicals Organic Part
Post by: superduper2009 on May 20, 2010, 01:34:23 am

how do u differentiate between aluminum and lead ions???
how do u differentiate between ketones and aldehydes???
how do u differentiate between the halogens???
how do u differentiate between sulfates and sulfites???
How do u test for carboxylic acids...
how do u test for alkanes and alkenes?
thanks in advance :D

Title: Re: Chemistry Practicals Organic Part
Post by: Darth Austrakast on May 20, 2010, 04:34:24 am

for alkanes and alkenes,
Alkanes turn brown bromine water colorless in UV light but not in dark............while alkenes decolorizes brown bromine water in both conditions.Also Alkanes are not oxidized by acidified K₂Cr₂O₇

For Carboxylic Acid u test with litmus and the acid turns it red.Also it reacts with Na₂CO₃ to form CO₂ that turns lime water milky

For aldehydes and ketones....well aldehydes produce a red precipitate with Fehling's solution or Benedict's solution while ketones remain unreacted

Well here are some attachments to help you out