alcohols

Question 1

solubility of alcohols

Answer 1

alcohols dissolve in water because the polar -OH group forms hydrogen bonds with water
solubility decreases as chain length increases as a larger proportion of the molecule is non-polar hydrocarbon

Question 2

boiling point of alcohols relative to alkanes

Answer 2

alcohols have higher boiling points than alkanes because hydrogen bonds form between molecules
these require more energy to overcome than induce dipole-dipole forces

Question 3

dehydration reaction of alcohols

Answer 3

reagents = H3PO4 catalyst
conditions = heat under reflux
forms an alkene and water

Question 4

what type of alcohols can undergo oxidation?

Answer 4

primary and secondary alcohols can undergo oxidation
tertiary alcohols cannot

Question 5

colour change when successful oxidation occurs

Answer 5

orange to green

Question 6

partial oxidation of a primary alcohol

Answer 6

reagents = acidified dichromate, H+/Cr2O7 2-
conditions = heat under distillation
forms an aldehyde -CHO

Question 7

complete oxidation of a primary alcohol

Answer 7

reagents = acidified dichromate, H+/Cr2O7 2-
conditions = heat under reflux
forms a carboxylic acid -COOH

Question 8

oxidation of a secondary alcohol

Answer 8

reagents = acidified dichromate, H+/Cr2O7 2-
conditions = heat under reflux
forms a ketone -CO-