Carboxylic Acids and Derivatives
Unit 4 - Jan 2010
Q1.
Which of the following methods may be used in a single step to make carboxylic acids?
   A     Hydrolysis of an ester with an alkali.
   B     Reaction of acidified potassium manganate(VII) with an alkene.
   C     Hydrolysis of a nitrile with hydrochloric acid.
   D     Reaction of an acyl chloride with ammonia.
(Total for question = 1 mark)

Q2.
Which of the following compounds would react with lithium tetrahydridoaluminate (lithium aluminium hydride) and also with phosphorus(V) chloride (phosphorus pentachloride)?
   A     CH3CH2CH2COOH
   B     CH3CH2COCH3
   C     CH3CHCHCH3
   D     CH2CHCH2CH2OH
(Total for question = 1 mark)

Q3.
In the synthesis of an ester, the use of an acyl chloride and an alcohol gives a better yield than the use of a carboxylic acid and an alcohol.
This is because the reaction between
   A     an acyl chloride and an alcohol is an equilibrium.
   B     an acid and an alcohol goes to completion.
   C     an acid and an alcohol requires a catalyst.
   D     an acyl chloride and an alcohol goes to completion.
(Total for question = 1 mark)

Q4.
Which of the following molecules is a methyl ester?
   A     CH3COOCH2CH3
   B     HCOOCH3
   C     CH3COCH2CH3
   D     CH3COCl
(Total for question = 1 mark)

Q5.
Which of the following reagents could be used to produce propanamide, CH3CH2CON2?
   A     Ammonia and 1-chloropropane
   B     Ammonia and propanoyl chloride
   C     Methylamine and 1-chloropropane
   D     Methylamine and propanoyl chloride
(Total for question = 1 mark)

Unit 4 - Jun 2010
Q6.
This question is about butanoic acid, CH3CH2CH2COOH.
(a)  Some reactions involving butanoic acid are shown below.

(i)  What type of reaction is Reaction A?
(1)
 ............................................................................................................................................. 
(ii)  Identify, by name or formula, the reagent which is used with sulfuric acid to carry out Reaction B.
(1)
 ............................................................................................................................................. 
(iii)  What reagent is used in Reaction C?.
(1)
 ............................................................................................................................................. 
(iv)  Name the organic product of Reaction D and write a balanced equation for its formation.
(2)
Name
 ............................................................................................................................................. 
Equation

(v)  Write the displayed formula for Z, the organic product of the reaction of butanoic acid with phosphorus(V) chloride, PCl5.
(1)
(b)  Butanoic acid and propane-1,2,3-triol are formed when fats in milk are hydrolysed. The presence of milk fat in low fat spreads is detected by hydrolysing the spread, and then analysing the products using gas chromatography (also called gas-liquid chromatography, GLC).
(i)  Explain why nitrogen, rather than oxygen, is used as the carrier gas in GLC.
(1)
 ............................................................................................................................................. 
 (ii)  What property determines whether butanoic acid or propane-1,2,3-triol would move faster through the chromatography column?
(1)
 ............................................................................................................................................. 
(c)  The formula of 3-hydroxybutanoic acid is shown below.

(i)  3-hydroxybutanoic acid can form a polymer which is used to make "green" packaging as it is biodegradable.

       Draw a section of this polymer, showing TWO monomer units. Clearly show any double bonds.
(2)

(ii)  The polymer cannot be used in acidic conditions. What reaction would occur when the polymer is in prolonged contact with an acid?
(1)
 ............................................................................................................................................. 
 ............................................................................................................................................. 
(Total for question = 11 marks)

Q7.
When the following reaction mixtures are warmed, which will contain ethanoic acid as one of the products?
   A     Ethyl methanoate and sodium hydroxide solution.
   B     Ethyl methanoate and dilute sulfuric acid.
   C     Methyl ethanoate and sodium hydroxide solution.
   D     Methyl ethanoate and dilute sulfuric acid.
(Total for question = 1 mark)

Q8.
Which of the following is a redox reaction?
   A     Ethanal reacting with Tollens' reagent.
   B     Ethanoyl chloride reacting with ammonia.
   C     Ethanoic acid reacting with ethanol.
   D     Ethanoic acid reacting with sodium hydroxide.
(Total for question = 1 mark)

Q9.
The following methods can be used to distinguish between pairs of organic compounds without further tests.
A     Warm each compound with Fehling's or Benedict's solution.
B     Add solid sodium carbonate to each compound.
C     Add 2,4-dinitrophenylhydrazine (Brady's reagent) to each compound.
D     Add water, drop by drop, to each compound.

(a)  Which test would distinguish propanone from propan-1-ol?
(1)
   A
   B
   C
   D

(b)  Which test would distinguish between aqueous solutions of ethanoic acid and ethanol?
(1)
   A
   B
   C
   D

(c)  Which test would distinguish ethanoyl chloride from ethanol?
(1)
   A
   B
   C
   D
(Total for question = 3 marks)

Unit 4 - Jan 2011
Q10.
The organic product of the reaction between ethanoyl chloride and methylamine has the formula

(Total for question = 1 mark)