Flashcards in Tests Deck (17):
Test for Aldehyde + equation
Tollen's reagent produces silver mirror
RCHO + [O] → RCOOH
Test for Ketone/Aldehyde
Brady's reagent produces orange precipitate
Test for Carboxylic acid + equation
2RCOOH + Na₂CO₃ → 2RCOONa + CO₂ + H₂O
Test for Alcohol + equation
Acidified potassium dichromate shows a colour change of orange to green
ROH + [O] → RCHO + H₂O.
ROH + 2[O] → RCOOH + H₂O.
Test for potassium
Flame test showing lilac colour.
Test for calcium
Flame test showing orange colour.
Test for sodium
Flame test showing yellow colour.
Test for copper
Flame test showing light blue colour.
Test for boron
Flame test showing green colour.
Test for Haloalkane
Heat with NaOH (aq) add ethanol and acidify with nitric acid. You then add silver nitrate solution to check for respective halogens from the colour of precipitate.
Test for Alkene
Mix with bromine water which changes the colour from orange to colourless.
Test for carbonate
React with acid and use calcium hydroxide to observe it going from clear to cloudy.
Recrystallise, dissolve impure solid in a minimum volume of hot water/solvent, cool solution and filter the solid, wash with cold water and dry.
Use a separating funnel to separate organic from aqueous solution. Dry with anhydrous salt like CaCl₂ and go through with redistillation.
The impure mixture is heated is then cooled and filtered through under reduced pressure.
Test for NH₄⁺ and Nitrate
Add warm NaOH and observe the gas turning the litmus paper blue.