Grade 12 Physical Sciences · Matter and Materials

Write esterification reactions

Write the reaction of an alcohol with a carboxylic acid to make an ester, and name the ester (ethanol + ethanoic acid → ethyl ethanoate).

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Reactions Organic Chemistry Grade 12 | Esterification, CombustionKevinmathscience

Esters Grade 12 Chemistry: All about esters & naming estersMiss Martins Maths and Science

Esterification Theory for Practical Gr 12Science With Cecile

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Question 4.1.4 · May/June 2022 · Paper 2 · National (DBE) · 2 marks

4.1 Study the following incomplete equations for organic reactions I and II.

Compounds P and Q are ORGANIC compounds and T is an INORGANIC compound.

I:

CH_{3} CH(CH_{3})CHBrCH_{3}

+ NaOH (conc.)

\to

P (major product) + NaBr + T

II:

CH_{3} COOH

+ compound Q

\to

butyl ethanoate +

H_{2} O

Answer the questions that follow. Diagram for question 4.1

4.1.4 For reaction II, write down TWO reaction conditions needed.(2)

Work it out on paper first. Then mark yourself with the official memo, one tick at a time.

More past paper questions: write esterification reactions

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3. Question 2.3.2 · November 2022 · Paper 2 · National (DBE) · 3 marks
A to F in the table below represent six organic compounds.
2.3 Compound F reacts with a carboxylic acid to form compound S in the presence of a strong acid.

Answer the questions that follow.
2.3.2 Write down the MOLECULAR FORMULA of the carboxylic acid.(3)
Show the memo (2 ticks)Memo
1. ✓
  Molecular formula of S $M (C_{3} H_{6} O) = 58$ g·mol $^{- 1}$
  
  $\frac{molecular mass of molecular formula}{molecular mass of empirical formula} = \frac{116}{58} = 2$
  
  Compound S $= C_{6} H_{12} O_{2}$
  1 mark · Determine empirical and molecular formulae
2. ✓
  Molecular formula of the carboxylic acid $C_{2} H_{4} O_{2}$
  2 marks · Write esterification reactions
4. Question 2.6.2 · May/June 2025 · Paper 2 · National (DBE) · 2 marks
The letters A to F in the table below represent organic compounds.
2.6 Ethanol reacts with compound C to form an organic compound Z.

Write down the:
2.6.2 STRUCTURAL FORMULA of compound Z(2)
Show the memo (2 ticks)Memo
1. ✓
  Functional group correctZ is ethyl butanoate. The ester functional group –COO– joins the butanoate part (4 C, from butanoic acid) to the ethyl part (2 C, from ethanol): C=O and C–O–C.
  1 mark · Write esterification reactions
2. ✓
  Whole structure correct $CH_{3} CH_{2} CH_{2} COOCH_{2} CH_{3}$ drawn with ALL bonds and H atoms shown (see the memo structure).
  1 mark · Draw structural formulae
5. Question 2.4.4 · November 2024 · Paper 2 · National (DBE) · 2 marks
The letters A to H in the table below represent organic compounds.
2.4 Compound F is formed when a carboxylic acid reacts with another organic compound, X, in the presence of a catalyst.

Write down the:
2.4.4 IUPAC name of compound X(2)
Show the memo (2 ticks)Memo
1. ✓
  Correct chain length and functional group, i.e. propanolPropanol
  1 mark · Write esterification reactions
2. ✓
  IUPAC name completely correct including numberingPropan-1-ol / 1-propanol
  1 mark · Write IUPAC names
6. Question 2.3.5 · November 2023 · Paper 2 · National (DBE) · 2 marks
The letters A to H in the table below represent eight organic compounds.
2.3 Write down the:
2.3.5 IUPAC name of the alcohol needed to produce compound B(2)
Show the memo (2 ticks)Memo
1. ✓
  Correct alcohol identifiedMethanol
  1 mark · Write esterification reactions
2. ✓
  Correct IUPAC form of the nameMethanol
  1 mark · Write IUPAC names

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