Test Tube Tests Flashcards
(40 cards)
Which type of molecules react with bromine water?
Alkenes
Which type of molecules react with acidified potassium dichromate?
1° alcohols
2° alcohols
Aldehydes
Which type of molecules react with Tollen’s reagent?
Aldehydes
Which type of molecules react with Fehling’s solution?
Aldehydes
Which type of molecules react with sodium carbonate?
Carboxylic acids
What is the reagent used to test for alkenes?
Bromine water
What reagent is used to test for primary and secondary alcohols?
Acidified potassium dichromate
Which reagents are used to test for aldehydes?
Acidified potassium dichromate
Tollen’s reagent
Fehling’s solution
Which reagent is used to test for carboxylic acids?
Sodium carbonate
What observation is made when bromine water reacts with an alkene?
Orange to colourless
What observation is made when acidified potassium dichromate reacts with a 1° alcohol?
Orange to green
What observation is made when acidified potassium dichromate reacts with a 2° alcohol?
Orange to green
What observation is made when acidified potassium dichromate reacts with an aldehyde?
Orange to green
What observation is made when acidified potassium dichromate reacts with a ketone?
No visible change / solution stays orange
What observation is made when Tollen’s reagent is reacted with an aldehyde?
Silver mirror formed
What observation is made when Tollen’s reagent is reacted with a ketone?
No visible change
What observation is made when Fehling’s solution is reacted with an aldehyde?
Brick red precipitate formed
What observation is made when Fehling’s solution is reacted with a ketone?
No visible change
What observation is made when sodium carbonate reacts with a carboxylic acid?
Effervescence
Why does bromine water go from orange to colourless when reacting with alkenes?
Electrophilic addition of Br2 to Alkene
Why does acidified potassium dichromate go from an orange to green solution when adding a 1° alcohol / 2° alcohol / aldehyde?
(Cr2O7)2- (orange) reduced to Cr3+ (green) when alcohol / aldehyde oxidised
Why does Tollen’s reagent form silver mirror when you react it with aldehyde?
Ag+ in Tollen’s reagent reduced to Ag(s) when aldehyde oxidised
Why is there no visible change when you react acidified potassium dichromate with ketones?
Ketones cannot be further oxidised
Why is there no visible change when you react Tollen’s reagent with ketones?
Ketones cannot be further oxidised
