organic tests

Question 1

how to test for alkenes

Answer 1

add bromine water and shake

Question 2

positive results for test for alkenes

Answer 2

orange bromine water goes colourless

Question 3

how to test for a halogenoalkane

Answer 3

1. add aqueous sodium hydroxide and gently warm.
2. acidify with nitric acid
3. add silver nitrate

Question 4

Positive result of a halogenoalkane

Answer 4

Precipitate will form
AgCl- white
AgBr- cream
AgI- yellow

Question 5

How to test for an alcohol

Answer 5

add acidified potassium dichromate

Question 6

Positive result for test for alcohols

Answer 6

Orange turns to green with a primary or secondary alcohol
No reaction with a tertiary alcohol

Question 7

How to test for an aldehyde (2 methods)

Answer 7

1. Warm with tollens reagent
2. Warm with fehlings solution

Question 8

Positive result for test for aldehyde

Answer 8

If tested with tollens- silver mirror forms
If tested with fehlings- Blue solution turns to a red precipitate

Question 9

How to test for a carboxylic acid

Answer 9

add sodium hydrogen carbonate