Identification Of Unknowns

Question 1

Water

Answer 1

All short chains will be soluble in water (alcohols, amines, Carboxylic acids, amides)
All other organic molecules will form 2 layers of water
Acyl chlorides react violently with water and EVERY AQUEOUS solution producing HCl gas!!!

Question 2

Blue litmus paper

Answer 2

Carboxylic acid turns it red
Can also test pH of gas formed

Question 3

Red litmus paper

Answer 3

Turns blue for an amine

Question 4

Metals or carbonates

Answer 4

Identifies acids (produces bubbles of gas)

Question 5

Bromine water

Answer 5

Alkene turns it from orange to colourless
Any alkane or alkyl chain slowly react in presence of UV light

Question 6

Permanganate

Answer 6

Reacts with primary alcohols and decolourises.
Primary alcohol forms Carboxylic acid.
Forms a brown precipitate with alkenes.

Question 7

Acidified Dichromate with heating

Answer 7

Oxidises primary alcohols
Orange dichromate turns green

Question 8

Tollens and Fehlings

Answer 8

Distinguish between aldehydes and ketones
Ketones DONT react
Fehlings goes from blue to brick red precipitate
Tollens goes from colourless to form a silver mirror,