carbonyl chemistry Flashcards
what is the reagent to test for alkenes and positive test
bromine water,
decolourises bromine water
what is the test for a carboxylic and positive test
Na2CO3 -
carbonate will see fizzing, CO2 gas produced
what is the test for a primary/secondary alcohol
H+/Cr2O7
orange —-> green
what is the test for phenol and positive test
universal indicator and Na2CO3,
red —> orange, no fizzing (weak acid)
what is the test for a haloalkane and positive test
AgNO3 (aq)
cl- white precipitate
br - cream precipitate
I - yellow precipitate
what is test for a Carbonyls ( aldehyde and ketone) and positive test
2,4 DNP
orange precipitate forms
What is test for an aldehyde and positive test.
what is half equation for formation of Ag
Tollens reagent (oxidation reaction)
produces a silver mirror.
Ag + e- —> Ag (s)
what reagent should be used to turn an aldehyde/ketone back to a primary alcohol/secondary alcohol, what type of reaction is this, what type of mechanism
reagent: aqueous sodium borohydride, NaBH4
this is a reduction reaction
nucleophilic addition
what is a nucleophile
donates a pair of electrons
what is the reagent needed to turn a carbonyl to a hydroxynitrile, (alcohol and CN group ) what is the mechanism
H+/NaCN
nucleophillic addition
2,4 DNP is added to an aldehyde or ketone an orange precipitate forms, how this be used to identify the specific compound
- recrystallise and dry the precipitate
- measure the melting point
- compare to known values
what are the 2 properties of carboxylic acids
dissolve in water
acids
why are carboxylic acids soluble in water
They can form hydrogen bonds to water molecules
why are carboxylic acids classed as acids
they can donate H+ ions, only weak acids though
what do carboxylic acids need to react with to make esters. What small product is formed
alcohol
conc H2SO4
H2O
