Alcohols - Exam Questions Flashcards
State why tertiary alcohols are not easily oxidised.
no hydrogen atom on the central carbon
State the test and result for an aldehyde.
Fehling’s solution - turns brick red
negative result = blue
State the advantages of making ethanol by the hydration of ethene.
- fast reaction
- pure product
- continuous cycle
State the disadvantages of making ethanol by the hydration of ethene.
- high technology
- expensive equipment
- ethene is from non-renewable resources
Outline a mechanism for the dehydration of alcohol to form an alkene in the presence of an acid catalyst.
H+ bonds with OH
OH2 breaks off - carbocation
CH breaks to form double bond - H+ ion + alkene
Give a suitable dehydrating agent for a dehydration reaction.
concentrated H2SO4
Name the types of reaction illustrated by:
glucose –> ethanol
ethanol –> ethene
- fermentation
- dehydration
State what must be added to an aqueous solution of glucose so that ethanol is formed.
yeast
Give one advantage of using ethanol as a fuel compared with using a petroleum fraction.
ethanol is renewable
Which reagent is required for the reaction of a haloalkane to form an alkene.
alcoholic hydroxide
State the purpose of the anti-bumping granules.
to prevent vigorous boiling
Name the mechanism for the dehydration reaction of an alcohol to form alkenes.
elimination
Identify a catalyst for the dehydration of ethanol to form ethene.
Concentrated H2SO4
Identify a catalyst and a reagent for converting a vegetable oil into margarine.
nickel + hydrogen
State what is meant by the term hydration.
addition of water
