Disadvantages of Route B (Nucleophilic subs with amine)
FURTHER SUBSTITUTION IS LIKELY
Suggest how you could show the atenolol produced by reduction of a ketone was a racemate and NOT a single enantiomer
shine plane polarized light
If racemate, no effect on plane polarized light as enantiomers rotate light opposite directions equally
State the property of Sulfur dioxide (gas) that causes pollution when it enters rivers
acid(ic) / acidity / produces H +
OR lowers pH
Draw a diagram to show the shape of a molecule of H2O Include any lone pairs of electrons.
State the H−O−H bond angle.
Explain this shape and bond angle.
104.5 degrees
lone pairs repel more strongly than bonding pairs
so bond angle reduced from/less than 109½° / tetrahedral
ALLOW reduced by 2.5° per lone pair or 5°
Suggest one reason why chlorobenzene (C6H5Cl) does not react with ammonia under normal conditions.
electron rich ring or benzene or pi cloud REPELS! nucleophile/ammonia
Organic Synthesis Exam Question
Give one disadvantage of Route A - sub with KCN, then reduction Ni + H2
Route A - lower YIELD because two steps
OR KCN is poisonous (3.8 spec) // Expensive LiAlH4
Route B - Nucleophilic substitution with excess ammonia
- Further reaction/substitution likely // impure product
Give one advantage and one disadvantage of manufacturing ethanol by fermentation rather than by hydration. Do not include energy consumption or cost.
ADVANTAGES
low technology
renewable feedstock / resource
allowed for use in drinks, perfumes
considered to be green
Give one advantage and one disadvantage of manufacturing ethanol by fermentation rather than by hydration. Do not include energy consumption or cost.
DISADVANTAGES
slow
low yield
significant land use (for growing sugar canes)
has to be distilled
(labour intensive?)
State one advantage and one disadvantage of the production of ethanol by the hydration of ethene compared to the fermentation of glucose.
ADVANTAGE
Fast reaction OR pure product
OR continuous process
OR cheap on manpower
OR high yield, 100% alcohol
State one advantage and one disadvantage of the production of ethanol by the hydration of ethene compared to the fermentation of glucose.
Disadvantage
High technology
OR ethene from non renewable source
OR expensive equipment not just costly
In the manufacture of margarine, unsaturated vegetable oils such as sunflower oil are hardened.
(i) State the reagent and conditions used in this process
Reagent = Hydrogen
Conditions - Nickel catalyst
Heat (100-200 degrees)
Nonane is often found in fuel for jet engines. Combustion in jet engines produces pollutants including nitrogen monoxide (NO). Explain how this nitrogen monoxide is formed. [2 marks]
M1 nitrogen and oxygen from air react
M2 at hightemperature (if temperature stated, over 1000C)
Use your understanding of properties of PVC to explain whether you'd expect a plasticiser in PVC used to insulate electrical cables [2 marks] = Need both ideas that
it is present
AND because PVC needs to be flexible / bendy
The characteristics of a homologous series, a series of compounds containing the same functional group
Any two from
chemically similar or chemically the same or react in the same way
same functional group
same general formula
differ from CH2
Explain what is meant by the term fuel
release (heat) ENERGY! (when burned) (1)
OR provides a (useable form of) energy
OR is a source of energy
Crude oil is separated into fractions by fractional distillation. Outline how different fractions are obtained by this process. [3 marks]
Crude oil is heated to vaporise it / oil VAPOURISED (1)
(Vapour passed into fractionating) tower / COLUMN (1)
Top of tower cooler than bottom or negative temperature gradient (1) OR condenses at different temperatures
fractions separated by boiling point
Use the data given above to explain why catalytic cracking of crude oil fractions is commercially important.
Identify shortfall in supply - e.g. petrol / small molecules (1)