4.3 alcohols and phenol

Question 1

reactions of alcohols
with hydrogen halides
lucas test- for tertiary alcohol

Answer 1

ROH + HX —-> RX + H20
treat alcohol with zncl2 catalyst and conc hcl
tertiary alcohols reaction quickly to form white ppt (insoluble)
secondary alcohols take longer to form primary alcohols won’t form ppt

Question 2

phenol structure

Answer 2

c6h50H

Question 3

structure of phenol

Answer 3

• interaction between delocalised electrons in the benzene ring and one of the lone pairs on the oxygen atom
• lone pair overlaps with delocalised electron ring system
• increases electron density

Question 4

reaction of phenol with bromine

Answer 4

phenol + 3br2 —-> 2,4,6 tribromophenol
substitution
orange to colourless
we make a white precipitate which smells of antiseptic cuz the molecule is large with VDW and is insoluble

Question 5

reaction of ethanoyl chloride and phenol
esterification with phenol

Answer 5

more reactive than c’acid
ethanoyl chloride + phenol —-> ester + hcl
ester is phenyl ethanoate

Question 6

test for phenol

Answer 6

add iron (lll) chloride
get an intense violet- purple solution