Tests Flashcards
Test for a primary alcohol
Observation
What is made
Add acidified potassium dichromate
Orange to green
Aldehyde (distillation)
OR
Carboxylic acid (heat under reflux)
Test for a secondary alcohol
Observations?
Add acidified potassium dichromate
Orange to GREEN
Ketone made
Test for a tertiary alcohol
Observation
Acidified potassium dichromate
No visible change (remains orange)
Test for haloalkanes
Observation
Add AgNO3 and HNO3
Chloro: white PPT
Bromo: cream PPT
Iodo: yellow PPT
Test for alkane
Bromine water remains orange
Test for alkene
Decolourises bromine water (orange -> colourless)
Tests for aldehyde
Silver mirror with Tollen’s Reagent
Red PPT with Fehling’s Solution
Orange to green in acidified potassium dichromate
Ketone + Tollen’s reagent
No visible change
Test for carboxylic acid
Observations
Add Sodium Carbonate
Fizzing
Test for Acyl Chloride
Add water to produce misty fumes of HCl
Test for Benzene
Add bromine water which will remain orange
Test for MgCl2
Add OH- ions
White PPT of Mg(OH)2 produced
Test for sulphate ions
Add BaCl2 and HNO3 to produce a white PPT
Test for Mg2+
Add NaOH
White PPT formed
Test for barium ions
Add sulphuric acid
White PPT formed
Test for halide ions
Observations
Add acidified AgNO3
F- : NVC
Cl-: white PPT
Br-: cream PPT
I-: Yellow PPT
Test for NH4+
Observations
NaOH
Warmth,
NH3 produced which turns litmus paper blue
How to further test halide ions
Add dilute NH3
Cl: PPT dissolves
Br: PPT partially dissolves
I: NVC
Then add concentrated NH3:
Cl: PPT dissolves
Br: PPT dissolves
I: no visible change
