Alcohols Flashcards
Alcohol to ketone
Reaction type - Oxidation
Reagent - potassium dichromate (K2Cr2O7) and H2SO4
Condition - Reflux or distillation
Alcohol to Aldehyde to Carboxylic acid
- Oxidation - K2Cr2O7 or H2SO4 - distillation
- Oxidation- K2Cr2O7 or H2SO4 - Reflux
Alcohol to Carboxylic acid
Oxidation - K2Cr2O7 or H2SO4 - Reflux, excess oxidising agent
Carbonyl group:
C=O
Aldehyde
Carbonyl bonded to at least one H atom
CHO
…al
Ketone
Carbonyl bonded to 2 C atom
CO
…one
Carboxylic Acid
Carbonyl bonded to an OH group
COOH
…oic acid
For all these reactions acidified K2Cr2O6 is used as the oxidising agent. K2Cr2O7 is orange and when it oxidises an alcohol the K2CR2O7 is reduced to Cr3+ which is green
What’s the observation for Alcohol
Oxidation?
Orange to green
Primary alcohol to aldehyde
Acidified Kr2Cr2O7
Heat under distillation
aldehyde to carboxylic acid
acidified K2Cr2O7
heat under reflux
oxidation of secondary alcohols
acidified K2Cr2O7
heat under reflex or distillation
how much [O] and H2O is used when Primary Alcohol to Aldehyde?
1 [o] and 1 H20
how much [O] and H2O is used when aldehyde to carboxylic acid?
1 [O] and 0 H2O
how much [O] and H2O is used when primary alcohol to carboxylic acid
2 [O] and 1 H2O
how much [O] and H2O is used when secondary alcohol to ketone
1 [O] and 1 H2O
features of a condenser
open at both ends
cold water flows around outside
purpose of condenser
condense any vapour and turns it back into a liquid
Antibumping granules
prevent large bubbles from forming so it boils smoothly
what happens to the aldehyde as it is produced during distillation?
the aldehyde boils/ vaporises and escapes from the reaction mixture to form a pure aldehyde
why is distillation used when producing an aldehyde from a primary alcohol
to get that vapour and cool back into a liquid to collect it right after in a collector for distillate
tollen’s reagent
reagent used - tollen’s
observation when aldehyde is present - silver mirror forms
observation when there is no aldehyde - NVC
Feling’s solution
observation when aldehyde is present - red ppt
not present - nvc
Carboxylic acid
reagent - Na2CO3 (sodium carbonate)
when carboxylic acid is present - effervesence
no carboxylic acid - NVC
