ORGANIC CHEMISTRY EXERCISE

Exercise 1

1. Complete the following table.

Name Molecular formula Structural Formula

CH3 −OH

Propan−1− ol

Propan−2−ol

Butan−1−ol

Butan−2−ol

Pentan−2−ol

2. Describe the process for converting sugar solution to ethanol

Name of process: ……………………………………………………………………………………...

Chemical equation: ……………………………………..……………………………………………

Conditions: ……………………………………………………………………………………….......

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3. Write down the chemical equation for the following reactions

(a) combustion of ethanol

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(b) combustion of propanol

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4. What are two uses of alcohols?

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5. If ethanol is exposed to air for a long time, it will turn sour. Explain why

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6. Compound D CH3CH2CH2OH Compound F(1) (2)

Conditions for (1) and (2):

(1) addition of steam and catalyst(2) reflux with acidified potassium dichromate(VI)

Name compounds D and F.What is reaction (2) known as?

Exercise 2

1. Complete the following table.

Name Molecular formula Structural Formula

2

Methanoic acid

CH3COOH

Propanoic Acid C2H5COOH

Butanoic acid

2. Carboxylic acids are weak acids. Explain the term ’weak acids’.

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3. Write down the chemical equations for the following reactions

(a) Ethanoic acid and sodium hydroxide

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(b) Propanoic acid and potassium carbonate

……… ……………………………………………………………………………………………….4. Carboxylic acids react with alcohols to yield a sweet smelling liquid. What is the name of the

sweet smelling liquid?

Name: …………………………………..

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H | O H – C – C | H O – H

H H H | | | O H - C – C – C – C | | | H H H O – H

State a use for this liquid

Use: ……………………………………………………………………………………..…………….

Write an equation showing the structural formulae for the formation of this liquid from propanoic acid and ethanol. Name all the substances.

5. Draw the structural formulae of the following

(a) Ethyl ethanoate

(b) methyl butanoate

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6. Alcohol S reacts with carboxylic acid T to form the ester propyl methanoate.

(a) Name the other product formed in the reaction.(b) Name alcohol S and carboxylic acid T.

Exercise 3

1(a). What is the empirical formula of the polymer with the following repeating unit ……………………………………………………………………………………………………………….

(b) Draw the structural formula of the monomer.

2. (a) Complete the following table.

MonomerPart of Polymer [ showing 3 repeating units ]

(i)

(ii)

(iii)

(iv)

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C CH

FH

F

C CH

CNH

H

C CCH3

HCl

H

C CH

FF

H

(b) Compare and contrast the two monomers and polymers in parts (a)(i) and (a)(ii). What are the similarities or differences between the two polymers formed?

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3. Given the following polymers, draw the structural formula of the monomer in the boxes provided.

(a)

b)

4. Draw a partial structure( at least 3 repeating units) to represent polypropene.

(a) What is the name and molecular structure of the monomer for polypropene?

Name: ...........................................

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C

H

H

C

Cl

H

C

H

H

C

Cl

H

C

H

H

C

Cl

H

C

H

H

C

Cl

H

C

H

H

C

Cl

H

C

H

Cl

C

H

C

H

Cl

C

H

C

H

ClHC

H

C

H

Cl

C

H

C

H

Cl

C

H

O

H

O

H

O

H

O

H

O

H

Structure:

(b) What is the empirical formula of polypropene? Is the empirical formula the same as propene?

5. Given that an addition polymer has 38.4 % by mass carbon and 56.8 % by mass chlorine. The rest being hydrogen. Determine the structure of the polymer.

Exercise 4

1. What is "condensation polymerisation"?

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2. Two examples of condensation polymers are Nylon and Terylene. Complete the table.

Partial structure of condensation polymer Name and structure of linkage

Uses

Nylon

Terylene

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3. Why is the disposal of non-biodegradable plastics a cause of environmental pollution?

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3. The material used for making soft drink and water bottles consists of the polymer PET. PET or PETE is the abbreviation for poly(ethylene terephthalate). It is produced by the reaction between ethylene glycol and terephathalic acid.

H − O − (CH2) − O − H Ethylene glycol

O O II II Terephathalic acid H − O − C − C6H4 − C − O − H

(a) What is the name for this type of reaction ? ………………………………………………….

(b) Write the structural formula, showing 2 repeating units, of PET.

4. Consider two compounds, X and Y, with the structural formula as shown below.

H H O O I I II II

H−N − (CH2)6 −N−H Cl − C − (CH2)4 − C − Cl

X Y

When X and Y react, a gas G and a compound Z, is produced.

(a) State the type of reaction that occurs between X and Y. ……………………………………..

(b) (i) Name gas G. ....………………………………………………………………………..….

(ii) During one industrial accident, gas G escapes into the air. Give one adverse effect of gas G on the environment.

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……………………………………………………………………………………………….

(c) (i) State one use, with reason, of compound Z.

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(ii) Draw the structural formula of compound Z. [ show 3 repeating units]

5. Nylon is a polyamide produced by condensation polymerization. 6.

(a) Describe the formation of nylon from monomers.Your answer should explain the terms polyamide and condensation polymer.

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(b) State one similarity and one difference between the structure of nylon and protein (Hint : read up on Wikipedia on proteins).

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(c) Nylon is non-biodegradable. What does this mean?

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(d) The monomers in protein can be identified using chromatography. Insulin is a protein used to treat people suffering from diabetes. In an experiment, insulin was broken down into a mixture of monomers. A chromatogram was set up with a sample of the mixture and samples of the monomers of proline and lysine (amino acids) as references.

(i) Explain with the aid of a diagram, how chromatography could be used to show that proline and lysine are present in the mixture.

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(ii) Explain why a locating agent needs to be used to identify the monomers.

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