4.2.1 Alcohol Flashcards
What is the functional group of an alcohol?
Hydroxyl group - OH
What is the general formula for alcohol?
C(n) H(2n+1) OH
How do you name alcohols (one prefix, one suffix)?
Hydroxyl or ol
What kind of intermolecular forces do alcohols have? Why?
Hydrogen bonding, due to the electronegativity difference in the OH bond
How do alcohols’ melting point and boiling point compare to other hydrocarbons’ of similar C chain lengths? Why?
Higher because they have hydrogen bonding
Are alcohols soluble in water? Why does solubility depend on chain length?
Soluble when short chain - OH hydrogen bonds to hydrogen bond in water
Insoluble when long chain - non polarity of C-H bond takes precedence
What makes an alcohol primary?
C bonded to OH is only bonded to one other C atom
What makes an alcohol secondary?
C bonded to OH is bonded to two other C atoms
What makes an alcohol tertiary?
C bonded to OH is bonded to three other C atoms
Write an equation for the combustion of ethanol
C₂H₅OH (l) + 3O₂ (g) -> 2CO₂ (g) + 3H₂O (l)
What forms if you partially oxidise primary alcohol?
an aldehyde
What conditions are needed to partially oxidise a primary alcohol?
Dilute sulphuric acid, pottasium dichromate (VI), distil product as its produced, gentle heating
Write the equation for the partial oxidation of ethanol
C₂H₅OH (l) + [O] -> CH₃CHO (g) +H₂O (l)
What forms if you fully oxidise a primary alcohol?
A carboxylic acid
What conditions are needed to fully oxidise a primary alcohol?
Concentrated sulphuric acid, pottasium dichromate (VI), reflux, strong heating
Write an equation for the full oxidation of ethanol
C₂H₅OH (l) + 2[O] -> CH₃COOH (g) + H₂O 9l0
What forms if you oxidise a secondary alcohol?
A ketone
What conditions are needed for the oxidation of a secondary alcohol?
Concentrated sulphuric acid, potassium dichromate (VI), strong heating
Write an equation for the oxidation of propan-2-ol
CH₃CH(OH)CH₃ (l) + [O] -> CH₃COCH₃ (g) + H₂O (l)
Is it possible to oxidise tertiary alcohol?
No
What is a dehydration reaction?
A reaction where water is lost to form an organic compound
What are the products of a dehydration reaction of alcohol?
Alkene and water
What are the conditions required for dehydration of alcohol?
Concentrated sulfuric acid or concentrated phosporic acid and 170°C
What are the products of the halide subsitiution reaction with alcohol?
Haloalkane and water
