Page 1

Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Org Chem Reactions - PART A Typical reactions of various functional groups A. Combustion -------------------------------for most organic compounds, esp. alkane and alkene

p.2

Answer: p.5

B. Substitution reaction ----------------------- p.6 for alkane (p.6), haloalkane (p.10) and alkanol (p.11)

Answer: p.9 and p.12

C. Cracking ----------------------------------for LARGE alkane

Answer: p.15

D. Addition reaction -------------------------for alkene (+X-X : p.17 +X-Y : p.21 )

p.13 p.16

Answer: p.20 and p.22

E. Dehydration -------------------------------

p.24

F. Oxidation ----------------------------------

p.27

for alkanol

Answer: p.26

for alkanol and aldehyde

Answer: p.34

G. Reduction ---------------------------------for ketone, aldehyde and alkanoic acid

p.35

Answer: p.36

H. Esterification ------------------------------- p.36 for alkanol, alkanoic acid

Answer: p.39 and p.42

I. Hydrolysis ---------------------------------- p.43 for ester (p.43) and amide (p.47)

Answer: p.46

J. Amide formation --------------------------- p.48 for alkanoic acid

Answer: p.49

K. Addition polymerization ------------------- p.50 for alkene

Answer: p.57

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 1


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

A. Combustion

dry cobalt chloride paper from blue to pink

limewater from colourless to milky

Liquid X turns

Gas Y turns

What are the products formed after combustion of hydrocarbon? Liquid X is ______________ and Gas Y is ___________ _________________. Write down a chemical equation for the complete combustion of each of the following hydrocarbons. (a) CH4

+

+

(b) C4H10

+

+

(c) C8H18

+

+

Skills: “先balance C, 再balance H, 最後balance O”

Large number of carbon atoms (high carbon content): * very difficult (d) *C16H34

+

+

(e) *C32H66

+

+

[02CE/MC#34] Upon complete combustion, gaseous hydrocarbon X gives an equal number of moles of carbon dioxide and water. Which of the following hydrocarbons may X be? *Balancing the equations first! (1) ethane (2) ethene, C2H4 (3) propene, C3H6 A. B. C. D.

(1) only (2) only (1) and (3) only (2) and (3) only Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 2


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

A hydrocarbon X is burnt in air as shown in the following set-up:

(a)

What is the colourless liquid Y?

(b)

Suggest a test to identify Y. Write also the expected observations.

(c)

What happens to lime water? Write a chemical equation for the reaction in lime water.

(d)

*It is found that 1 mole of X requires 3.5 mole of O2 for complete combustion. Give the molecular formula of X and write a chemical equation for its combustion in air. *Balancing the equations first!

Complete combustion Carbon dioxide, CO2

Water, H2O

Conditions

Observation

Enough oxygen supply

non-sooty blue flame

When a CnH2n+2 is burnt… Incomplete combustion Carbon monoxide, CO Water, H2O Carbon particulates, C Unburnt hydrocarbons

 Not enough oxygen supply  Large number of carbon atoms / high carbon content

yellow sooty flame

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 3


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Under different conditions, a hydrocarbon X with formula C10H22 may burn according to the following equations. (I)

C10H22 + 31/2 O2  10CO2 + 11H2O

(II)

C10H22 + 19/2 O2  4C + 4CO + 2CO2 + 11H2O

(a)

Under what condition does X burn according to equation (I)?

(b)

Under what condition does X burn according to equation (II)?

(c)

What do you observe when X burns according to equation (II)?

(d)

Suggest two harmful effects of the reaction represented by equation (II).

[05CE/5(b)/2 marks] Both pentane (C5H12) and octane (C8H18) are members of the same homologous series (i.e. alkanes). Which compound, pentane or octane, will burn with more sooty flame? Explain your answer.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 4


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: Liquid X is Water and Gas Y is carbon dioxide. (a) CH4

+

2 O2

2H2O

+

CO2

(b) C4H10

+

13/2 O2

5H2O

+

4CO2

(c) C8H18

+

25/2 O2

9H2O

+

8CO2

(d) C16H34

+

49/2 O2

17H2O

+

16CO2

(e) C32H66

+

97/2 O2

33H2O

+

32CO2

D (a) (b)

(d)

water use dry cobalt chloride paper paper will turn from blue to pink turns to milky from colourless Ca(OH)2 + CO2  CaCO3 + H2O C2H6 + 3.5O2  2CO2 + 3H2O

(a) (b) (c) (d)

enough oxygen supply not enough oxygen supply sooty flame CO is toxic; C particulates will irritate breathing system

(c)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 5


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Substitution reaction between alkane and bromine:

B. Substitution

brown

CH4 + Cl2

CH3Cl + HCl

UV light

CH3Cl + Cl2

UV light

CH2Cl2 + HCl

CH2Cl2 + Cl2

UV light

CHCl3 + HCl

CHCl3 + Cl2

UV light

CCl4

+ HCl

Reagent, condition

Observation

Cl2(g), light

from greenish-yellow to colorless

Excess methane: chloromethane

Excess chlorine: CH2Cl2 dichloromethane CHCl3 trichloromethane CCl4 tetrachloromethane

Br2 in CH3CCl3, light

from reddish-brown to colorless

Excess methane: bromomethane

Excess bromine: CH2Br2 dibromomethane CHBr3 tribromomethane CBr4 tetrabromomethane

***NO SUBSTITUTION IN DARK*** [08CE/MC#24] When chlorine reacts with methane under sunlight, which of the following compounds can be formed? (1) chloromethane (2) dichloromethane (3) hydrogen chloride A. B. C. D.

(1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3)

Products

* Rate

of reaction: Cl2 is faster than Br2

[03CE/MC#33] Ethane reacts with bromine under suitable conditions. Which of the following statements concerning this reaction is/are correct? (1) The reaction occurs readily in the dark. (2) The reaction is a substitution. (3) The reaction gives a mixture of organic products. A. B. C. D.

(1) only (2) only (1) and (3) only (2) and (3) only

[99CE/MC#44] Which of the following statements concerning the reaction of an alkane with bromine are correct? (1) The reaction occurs faster under sunlight than in darkness. (2) The reaction is a substitution reaction. (3) The colour of the reaction mixture fades. A. B. C. D.

(1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3) Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 6


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Which of the following are substitution reactions? (1) CH4 + 4Cl2  CCl4 + 4HCl (2) CH4 + 2Cl2  C + 4HCl (3) CH2Br2 + Br2  CHBr3 + HBr A. B. C. D.

(1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3)

Which of the following experiments gives an observable change when the test tubes are exposed to diffuse sunlight? A.

B. hexane + Br2 in methylbenzene (also an organic solvent)

hexane + acidified KMnO4 solution

C.

D. hexane + acidified K2Cr2O7 solution

hexane + conc. H2SO4

A student wanted to study the reactions of alkanes and alkenes with halogens. (a) The student first added a few drops of hexane to bromine solution (in an organic solvent) in darkness. Describe what would be observed.

(b) The student then repeated the procedure in (a) in sunlight. Describe the expected observations.

(c) Describe what would happen if bromine solution had been replaced by chlorine solution (in an organic solvent) for the experiment in (b).

(d) The student added a few drops of liquid hex-1-ene to bromine solution in darkness. Describe what would be observed. Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 7


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

An experiment is done with two boiling tubes A and B containing bromine dissolved in a non-aqueous solvent and methane. Boiling tube A is wrapped with aluminum foil and boiling tube B is unwrapped. Both of them are

put under diffused sunlight.

After half and hour, the aluminum foil is removed and the two boiling tubes are examined. (a) What do you observe in the two boiling tubes? Explain the observations.

(b)

CH3Br is formed in one of the tubes. In which boiling tube is CH3Br formed? Write an equation for the formation

(c)

Is this a good method to prepare CH3Br? Explain.

(d)

The following pairs of reagents undergo reaction under diffused sunlight at different rates. Arrange them in descending order of the vigor of the reaction. Explain your answer. (1) (2) (3)

CH4 and Br2 CH4 and Cl2 C2H6 and Br2

[12DSE/paperI/15/3 marks] Use electron diagrams to illustrate, step by step, how CH4 reacts with Br2 under sunlight to form CH3Br. (Show electrons in the outermost shells only.)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 8


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: D D D B B (a) (b) (c) (d)

No observable change. Bromine turns from brown to colorless slowly. Chlorine solution turned from pale green to colourless rapidly. Bromine turns from brown to colorless rapidly.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 9


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

B. Substitution

Reactivity: RF < RCl < RBr < RI

where X is halogen atom e.g. Cl, Br and I, R is the alkyl group

Reagent, condition

Products

NaOH(aq) heat

Experimental set-up: heating

under reflux

Use of anti-bumping granules: Purpose for heating under reflux:

for smooth boiling prevent loss of volatile reactants

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 10


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

B. Substitution

Method 1 Reagent, condition Lucas reagent:

Observation

ZnCl2 in conc. HCl

Method 2

Which of the following compounds is/are secondary alcohol(s)?

A. B. C. D.

(2) only (1) and (3) only (1), (2) and (3) only (1), (2), (3) and (4)

Which of the following can be used to distinguish between hexan-1-ol and hexan-2-ol? A. K2Cr2O7 / H+ B. Conc. HCl / ZnCl2 C. PCl3 D. NaOH(aq)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 11


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Consider the following reaction: CH3CH2CH2OH ď&#x192; CH3CH2CH2Br (a)

Describe the experimental procedure, giving the reagent(s) required, for the formation of 1bromopropane from propan-1-ol.

(b)

How can you separate 1-bromopropane from the reaction mixture? Explain the principle of your method.

Suggest a chemical test to distinguish one compound from the other in the following pair. Your answer should include the reagents used and the observations expected. Give also appropriate equations. OH | CH3CH2CH2OH and CH3CHCH3

Answer: Propan-1-ol

Propan-1,3-diol

BB (a) Add a mixture of NaBr and conc. H3PO4 to propan-1-ol. Heat under reflux. (b) Fractional distillation Because 2-bromopropane is less polar which has a lower boiling point than that of propan-1-ol. 2. Test (1) Observation (1) Equation (1) Add ZnCl2 (in conc. HCl) to two liquids

gives turbidity in a few minutes; has no observable change.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 12


Topic XI – Chemistry of Carbon Compounds (Part A)

C. Cracking

C34H70 C17H36

 

by Ricky Tsui

: a chemical reaction to breakdown a large hydrocarbon into smaller alkanes and alkenes by heat with help of catalyst in the absence of air

C17H__ C__H__ (g)

+ +

C__H__ C13H26 CnH2n

CnH2n+2

Reactant: Large alkane Importance Conditions Other:

Product(1) : Smaller alkanes

Product(2): Smaller alkenes

Produce extra petrol

Produce raw materials for plastics

High temperature

 Porous pot as catalyst

Safety precaution – to prevent sucking back  We need to remove the delivery tube before stop heating.

[05CE/MC#2] Upon cracking, one molecule of decane (C10H22) gives two molecules of propene and one molecule of an alkane (X). What is X? A. B. C. D.

 No oxygen

*Product(3): Hydrogen gas (also possible)

[02CE/MC#9] Which of the following equations represents a cracking reaction? A. B. C. D.

C4H6 C4H10 C7H14 C7H16

C16H34  2C8H16 + H2

C4H8 + H2 → C4H10 C4H10 → C3H6 + CH4 C6H12O6 → 2C2H5OH + 2CO2 C4H9OH → C4H8 + H2O

[12DSE/paper1/2(a)/2 marks] Poly(ethenyl ethanoate) is a polymer (a kind of plastics). (a) Ethene is the raw materials used in making ethenyl ethanoate. Ethene can be produced from hydrocarbons of higher molecular mass by an important industrial process. (i) Name this industrial process. (ii) Explain why this process is important. Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 13


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[07CE/2(a)/3 marks] A student performed an experiment to crack paraffin oil and collect the gaseous products by using a boiling tube. (a) Draw a labelled diagram to show how this experiment can be performed in the laboratory.

[99CE/9(b)(i)(iii)/2 marks] Cracking of naphtha gives alkane X (relative molecular mass 44), alkene Y (relative molecular mass 42) and other products. (i)

What is the meaning of the term 'cracking'?

(iii)

Deduce the molecular formula of Y.

[00CE/8(a)(ii)/3 marks] Crude oil is a mixture consisting mainly of alkanes. Fractional distillation of crude oil gives different petroleum fractions. The table below lists the length of carbon chain of the alkanes in some of the fractions. Fraction Length of carbon chain Petrol/naphtha C5 – C10 kerosene C11 – C18 diesel C18 – C25 X C20 – C34

(ii)

(1)

Explain why the global demand for petrol is greater than that for kerosene.

(2)

Cracking kerosene can produce petrol. State the conditions required for the cracking process.

..

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 14


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: C34H70  C17H36 + C17H34 C17H36  C4H10 + C13H26 B B

( Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 15


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

D. Addition reaction Alkene contains C=C bonds

X2 or XY

[unsaturated hydrocarbon]

Product(s) [saturated hydrocarbon]

Addition reaction Two types of addition reaction:

[01CE/MC#32] The formulae of three straight-chain hydrocarbons are listed below: (1) C2H6 (2) C3H6 (3) C4H8 Which of these hydrocarbons is/are unsaturated? A. B. C. D.

(1) only (2) only (1) and (3) only (2) and (3) only

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 16


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

ď&#x201A;&#x152; Reaction with halogen: For example, Br2(l) or Cl2(g)

Differences between these two reactions: Reagent, condition

Br2 in 1,1,1-trichloroethane

Cl2 (g)

Observation

From brown to colorless

From greenish-yellow to colorless

Rate

Slower

Faster

Product name

1,2-dibromoethane

1,2-dichloroethane

[06CE/MC#16] Which of the following compounds is formed from the reaction of propene with chlorine?

Cl H H A.

Cl

H H H

C C C H

C.

Cl

H H H

H H H

H Cl H B.

Cl

H Cl H

C C C H

D.

H C C C H

H H H Examine the following diagrams: A:

C C C Cl

H Cl H

B:

C:

What type of reaction is taking place when compound A, B and C react with bromine dissolved in methylbenzene in the dark? Write equations for the reactions. Types of reaction: _____________ _____________ A:

B:

C:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 17


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

ď&#x201A;? Reaction with cold alkaline potassium permanganate solution:

*Acidified KCr2O7 cannot be used

since it is a weak oxidizing agent. An alkene can turn cold

alkaline potassium permanganate solution from purple to colorless rapidly. [08CE/MC#13] Which of the following statements concerning the reaction between acidified potassium permanganate solution and excess propene is INCORRECT? A. B. C. D.

The oxidation number of manganese changes from +7 to +2. The reaction occurred is an addition reaction. The acidified potassium permanganate solution is decolourised. The structure of the organic product is CH2(OH)CH2CH2OH.

When acidified potassium permanganate solution is added to but-2-ene, the compound formed is A. B. C. D.

butane-1,2-diol. butane-1,3-diol. butane-1,4-diol. butane-2,3-diol.

Chemical equation:

Observation:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 18


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Write equations for the reactions of propene with the following substances. (a)

Bromine dissolved in methylbenzene

(b)

Acidified potassium permanganate

(c)

Oxygen

ď&#x201A;&#x17D; Reaction with hydrogen

[03AL/paperII/5(c)(i)/2 marks] Hardening of vegetable oils can be done by hydrogenation. Explain.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 19


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: D

B

Addition reaction A:

B:

C:

D D (a)

(b)

(c)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 20


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

D. Addition reaction

Alkene + HX [Markownikoffâ&#x20AC;&#x2122;s rule (M-rule)]

H

H H

H

CH3

H

+ H-X

HH H

C 3 CH CH3 HH CH3CH

H CH3

X Example:

It states that in the addition of HX to an unsymmetrical alkene, the hydrogen atoms adds to the carbon atom of the carbon-carbon double bond that already has the greater

number

of hydrogen atoms.

[05CE/MC#4] What is the type of reaction involved when hydrogen bromide reacts with ethene to form bromoethane ? A. addition B. cracking C. polymerization D. substitution

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 21


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[04AL/paperII/6(b)(i)/2 marks] Hydrocarbon G reacts with HBr to give J as the major product. CH3CH2

C

C

H3C

CH2CH3

+

HBr

J

H G

Give the structure of J and its systematic name.

[01AL/paperI/5(a)(i)/1 mark] Consider the following reaction: CH3CH2

C

CH3 DBr

C H

H

(D is deuterium, an isotope of hydrogen.) Draw the structure of the major product.

[07AL/paper I/5(a)(ii)/1 mark] Give the structure of the major organic product E in the following reaction. HI(g)

E

E:

Answer: A 2-bromobutane

2-bromo-2-methylbutane

2-bromo-2-methylbutane

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 22


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Alkene + bromine water, Br2(aq)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 23


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

E. Dehydration

Name for the major product: ___________________________________

Try this!

[12DSE/MC#33]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 24


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 25


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: 2-methylbut-2-ene B

(a) Al2O3 (b)

(c)

Add Br2 in 1,1,1-trichloroethane in the dark Color change from brown to colorless rapidly. Add into acifified potassium permanganate solution. Color change from purple to colorless.

(d)

Learn more: dehydration of alkanol by:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 26


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

F. Oxidation

Reagent, condition Strong oxidizing agent: KMnO4 / H+ heat Weak oxidizing agent: K2Cr2O7 / H+ heat

Observation

from purple to colorless

from orange to green

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 27


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

To distinguish between 1o (2o) and 3o alcohol

Alkanol K2Cr2O7/H+ KMnO4/H+ Lucas reagent, ZnCl2 in conc. HCl

1o alcohol

2o alcohol

3o alcohol

 orange to green  purple to colorless

 orange to green  purple to colorless  Give turbidity in a few minutes

 No observable change

  Give turbidity immediately

To distinguish between 1o, 2o and 3o alcohol

[12DSE/MC#29]

[12DSE/MC#28]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 28


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Consider the following two molecules:

Which of the following statements about the two molecules is/are correct? (1) Both turn dichromate from orange to green (2) Both can be dehydrated to give same major product. (3) Both react with Lucas reagent to give cloudiness A. (3) only B. (1) and (2) only C. (2) and (3) only D. (1) and (3) only

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 29


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Orange ppt. Carbonyl group

-zine

-zone To identify the carbonyl group (aldehyde / ketone)

Aldehyde

Ketone

Carboxylic acid

2,4dinotrophenlyhydrazine

 Orange ppt.

 Orange ppt.

Tollens’ reagent,

 Silvery mirror is formed

 Gas bubbles produced

ammonical silver nitrate solution

NaHCO3 or Mg(s)

To identify the aldehyde

To identify

compound only

carboxylic acid

*K2Cr2O7/H+ *KMnO4/H+

 orange to green  Purple to colorless

* Aldehyde can be oxidized to carboxylic acid, but ketone cannot, but this cannot be used to identify the aldehyde compounds because 1 o and 2o alcohol can do also.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 30


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Experimental set-ups for oxidation of alcohol and collection of product:

a

Alkanol  Aldehyde

3 Alkanal has a lower boiling

Single step

point, can be separated by

simple distillation.

2 1

b

Alkanol  Aldehyde  Alkanoic acid

Step 1

Step 2 3

Distillate 

alkanoic acid 2

heat

1

Heat under reflux

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 31


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Which of the following can be used to distinguish between propanal and propanone? (1) K2Cr2O7/H+ (2) LiAlH4 / ether followed by H3O+ (3) Br2(aq) A. B. C. D.

(1) only (2) only (1) and (3) only (2) and (3) only

Which of the following can be used to distinguish between CH3COOCH3 and CH3CH2COOH? (1) Water (2) Ether (3) Mg ribbon A. B. C. D.

(1) and (2) only (1) and (3) only (2) and (3) only All of the above hint: ether is a solvent that can dissolve both acid and ester

Consider the following two reactions: (1) CH3CH2OH

CH3CHO

(2) CH3CH2OH

CH3COOH

(a) Draw the experimental set-up for the formation and collection of CH3CHO as stated in equation (1).

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

(b) Under different conditions, CH3CH2OH can be oxidized to CH3COOH as stated in equation (2). (i) Sate the necessary conditions for the formation and collection of CH3COOH.

(ii)

Explain why different products are formed under different conditions as stated in equation (1) and (2).

(c) Suggest a chemical test, stating the reagent(s) used and expected observations, to distinguish the products formed in equations (1) and (2).

[12DSE/paper2/3/8 marks]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer: D D C A B (a)

(b)

(c) Any one of the following tests and observations:  Add 1,2-dinitrophenylhydrazine solution. Ethanal reacts to give orange precipitate but ethanoic acid does not.  Add Tollens’ reagent. Ethanal reacts to give silver mirror on the wall of test tube but ethanoic acid does not.  Add acidified potassium dichromate solution. Ethanal turns the orange solution to green but ethanoic acid does not.  Add NaHCO3 solution. Ethanoic acid reacts to give out gas bubbles but ethanol does not.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

G. Reduction

Try this!

Write the chemical equation and name the product formed:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Propan-1-ol (primary alcohol)

Propan-2-ol (secondary alcohol)

Propan-1-ol (primary alcohol)

H. Esterification

n-1

n'

ethyl propanoate

propyl ethanoate

*methyl methanoate

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

More ester examples:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[12DSE/MC#34]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer:

ethyl propanoate

propyl ethanoate

*methyl methanoate

D

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Experimental set-up for esterification:

[04CE/9(b)/3 marks] An ester can be prepared by heating an alkanol with an alkanoic acid under reflux in the presence of concentrated sulphuric acid. (i)

Draw a labelled diagram to show the set-up used in heating the reaction mixture under reflux.

(ii)

Suggest ONE reason why it is necessary to heat the mixture under reflux.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[06CE/2/5 marks] X, Y and Z are organic compounds. The flow diagram below shows the conversions of X to Z.

(a)

Z has a pleasant smell and its molecular formula is C4H8O2. Draw the structure of Z.

(b)

To which homologous series does Y belong?

(c)

Give the systematic name of X.

(d)

State the expected observation when X reacts with acidified potassium dichromate solution.

(e)

State the function of concentrated sulphuric acid in the reaction of Y with methanol.

[01CE/3(c)/2 marks] (i)

Why is butyl butanoate used in the drink?

(ii)

Suggest how butyl butanoate can be prepared in the laboratory.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

I. Hydrolysis

A acidic hydrolysis heat /

B alkaline hydrolysis

+ H+(aq)

heat

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[05CE/11(a)(i)/1 mark] The equation below shows the conversion of vegetable oil X to methyl carboxylate Y and alcohol Z :

Draw the structure of Z.

[02AL/paperII/6(c)(i)/1.5 marks] Both compounds K and L are natural fats that exist in human body. CH2 OCO(CH2)16CH3 CHOCO(CH2)7CH=CH(CH2)7CH3 CH2 OCO(CH2)16CH3 K CH2OCO(CH2)16CH3 CHOCO(CH2)3(CH=CHCH2)4(CH2)3CH3 CH2OH L

Draw structures of all products formed from the complete hydrolysis of K.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Application of alkaline hydrolysis of ester

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer:

Triglycerol

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Acidic hydrolysis

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

J. Amide formation Instead of SOCl2, PCl3 and PCl5 can also be used.

Consider the following two reactions:

(a) Give the structures and systematic names for A and B. A:

B:

(b) Give the structure for C. C:

[09AL/paperI/4(a)/2 marks] Lysergic acid diethylamide (LSD) can be synthesized from lysergic acid in two steps as shown below:

What are reactants D and E? D:

E:

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer:

C:

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Page 49


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

K. Addition polymerization

“Monomer”

“Polymer”

“Repeating unit”

Write a chemical equation for the formation of polyethene. (Monomer: ethene, a 2C alkene).

“Monomer”

“Polymer”

“Repeating unit”

Write a chemical equation for the formation of polypropene. (Monomer: propene, a 3C alkene).

“Monomer”

“Polymer”

“Repeating unit”

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 50


Topic XI – Chemistry of Carbon Compounds (Part A) Polymer

Monomer

Repeating unit

Polymer formula

by Ricky Tsui

Uses

LDPE: plastic bags and food wraps

Polythene (Polyethene)

HDPE: water buckets

making helmet

Polypropene

Polystyrene: feeding bottles

Polystyrene

Expanded polystyrene: Lunch box

Pipes and raincoats PVC (Polyvinyl chloride)

Glass substitutes Perspex

Making ‘non-stick’ frying pan

Teflon

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[12DSE/MC#21]

[10CE/MC#10]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 52


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) [00CE/MC#15] polymer has the following structure:

by Ricky Tsui

[04CE/MC#15] The structure of polymer X can be represented by

What is the monomer of this polymer? A. B. C. D.

butane but-1-ene but-2-ene 2-methylpropene

[04CE/MC#41] Which of the following statements concerning polyvinyl chloride (PVC) are correct? (1) PVC is used in making raincoats. (2) PVC softens upon gentle heating. (3) When PVC is strongly heated, fumes with an irritating odour are emitted. A. B. C. D.

What is the monomer of X? A. B. C. D.

1,1-dimethylethene 1,2-dimethylethene methylpropene but-1-ene

[02CE/MC#20] The monomer of polymer X is chloroethene. Which of the following statements concerning X is correct? A. B. C. D.

X is a condensation polymer. X is a thermosetting plastic. X is used in making drainage pipes. The repeating unit of X is as follows:

(1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3)

[01CE/MC#9] Which of the following statements concerning uses of plastics is correct? A. B.

Perspex is used for making ash trays. Polyvinyl chloride is used for making raincoats. C. Polystyrene is used for making floor tiles. D. Nylon is used for making packing materials for electrical appliances.

[01CE/MC#17] Which of the following compounds is a monomer of polyvinyl chloride (polychloroethene)? A. B. C. D.

CH2=CHCl CH2=CCl2 CHCl=CHCl CCl2=CCl2

[07CE/MC#9] Which of the following items can be made from polystyrene? A. clothing B. food wrap C. electric socket D. packaging material

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[00CE/MC#38]

Some concentrated sulphuric acid was poured into a sink connected to a catchpot made of polyvinyl (PVC). After some time, the catchpot became deformed. Which of the following explanations for the deformation of the catchpot is/are correcr? (1) The heat liberated when the concentrated sulphuric acid mixed with the water in the catchpot caused PVC to soften. (2) PVC was decomposed into its monomers by the concentrated sulphuric acid. (3) PVC was oxidized by the concentrated sulphuric acid. A. B. C. D.

(1) only (2) only (1) and (3) only (2) and (3) only

[99CE/MC#41] Plastic X has the following structure:

Which of the following statements concerning X are correct? (1) The monomer of X is CHCl=CHCl. (2) X can be used to make electric sockets. (3) The flue gas produced by the incineration of X can cause the formation of acid rain. A. B. C. D.

(1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3)

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[06CE/11(b)(i)/1 mark] Plastics can be classified into thermoplastics and thermosetting plastics according to their thermal properties. Polyethene (PE) is a thermoplastic commonly used in making shipping bags. Such bags are durable. Write the chemical equation for the formation of PE from its monomer.

[01CE/7(a)(i)-(iii)/3 marks] (2) (a) Polyethene is used in making shopping bags and its monomer is ethene. (i) Draw the electronic diagram of ethene, showing electrons in the outermost shells only.

(ii)

(iii)

Name the type of polymerization involved in the production of polyethene.

State ONE property of polyethene that makes it suitable for making shopping bags.

[99CE/9b(iv)(1)/1 mark] Cracking of naphtha gives alkane X (relative molecular mass 44), alkene Y (relative molecular mass 42) and other products. Y can be used as a starting material for the production of plastic Z. Write the chemical equation for the formation of Z from Y. [09CE/4(a)(b)(i)/2 marks]

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

[07CE/8(a)/3 marks] Teflon is a plastic that can be used to make artificial hip joints. Teflon is an addition polymer of linear structure consisting of carbon and fluorine only. The ratio of the number of carbon atoms to the number of fluorine atoms in the polymer is 1 : 2. (i)

Draw a portion of the Teflon structure with 10 carbon atoms.

(ii)

Write the repeating unit of Teflon, and suggest a possible monomer of Teflon. Repeating Unit:

Monomer:

[05CE/6(a)/2 marks] Polystyrene is a plastic with a wide range of uses. It has the following structure :

(i)

Draw the structure of styrene, the monomer of polystyrene.

(ii)

Suggest why polystyrene does NOT have a constant relative molecular mass.

[08CE/8(a)(b)/2 marks] The active ingredient of a superglue has the following structure: H

CN C C

H

C OCH3

O Superglue can join objects together quickly through the polymerization of the active ingredient in the presence of water vapour.

(a)

Name the type of polymerization that the active ingredient undergoes.

(b)

Write a chemical equation for the polymerization involved.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Answer:

A B

D A

C D

C A

D B

C

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Org Chem Reaction - PART B Inter-conversions of carbon compounds

DONâ&#x20AC;&#x2122;T try hard to memorize all of them! Understand the nature of reaction + practice!

Five types of questions: 1. 2. 3. 4. 5.

product(s) prediction suggest reagent(s) and condition(s) suggest a synthetic route (not more than three steps) experiment (long question) percentage yield (%)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) 1.

[10AL/paper II/4(c)/3 marks]

by Ricky Tsui

product(s) prediction

Out of syllabus

E:

F:

G:

[07AL/paper I/5(a)(ii)/1 mark] 5.

(a)

Give the structure of the major organic product E in the following reaction. HI(g)

(ii)

E

E:

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Page 60


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) 2.

by Ricky Tsui

suggest reagent(s) and condition(s)

[04AL/paper I/5(a)(i)/1mark] 5.

(a)

Identify K in the following reaction: O

O

C-CH3

(i)

C-CH3

K

K: K : H2/Pt [02AL/paper I/5(b)(i)(iii)/2marks] 5.

(b)

Suggest reagent(s) to accomplish each of the following single-step transformations: O

(i)

OH

O

O

CH3CH(CH2)4COCH3

CH3C(CH2)4COCH3

CO2 H

CHO

(iii) COCH3

COCH3 OH

OH

(i)

(1) LiAlH4 / ether; (2) H3O+ (i) Cr2O72-/H+

[00AL/paper I/5(b)(i)(ii)/4marks] 5.

(b)

(i)

Give the reagents and conditions for the two steps of the conversion: OH

O N(CH3)2

CH3CH2-C

Step 1

CH3CH2-CH

A

N(CH3)2

Step 2

CH3CH=CH

N(CH3)2

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

3.

by Ricky Tsui

suggest a synthetic route (not more than three steps)

[12DSE/paper I/12(d)/2marks]

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Page 62


Topic XI – Chemistry of Carbon Compounds (Part A) 3.

by Ricky Tsui

suggest a synthetic route (not more than three steps)

[09AL/paper II/4(b)(ii)/3marks] (b)

Neoprene, a synthetic rubber, can be obtained from buta-l,3-diene via the following route:

(ii)

Suggest reactant(s) and conditions for each of Steps 2, 3 and 4.

Practice more! Outline a synthetic route, with no more than three steps, to accomplish the following conversion. For each step, give the reagent(s), reaction conditions (as appropriate) and the structure of the organic product. (a)

CH3CH2CH2Br  CH3CH2CH3

(b)

(C6H5)CH2CHO  (C6H5)CH2BrCH3

(c)

CH3CH2CH2CONH2  CH3CH2CH2CH2OCOCH3

(d)

(C6H5)CH3  (C6H5)CONH2 (this takes four steps)

(e)

CH3COCH2COOCH2CH3  CH3CHBrCH2CH2Br

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

(a)

(b)

(c)

(d)

(e)

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 64


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) Common setup 1 of 2: distillation

4.

by Ricky Tsui

experiment (long question)

[12DSE/paper I/12(c)/2marks]

[02AL/paperI/8(a)/2 marks] (a)

In an attempt to prepare 1-methylcyclopentene, 1-methylcyclopentanol was allowed to react with phosphoric(V) acid. The reaction mixture was then subjected to simple distillation. (i)

Draw a labeled diagram to show the set-up of apparatus used in a simple distillation.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 65


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

Common setup 2 of 2: heat under reflux

4.

by Ricky Tsui

experiment (long question)

[06AL/paperI/8(a)(ii)/2 marks] 8.

(a)

A mixture of two 2,3-diphenylpropenoic acids (G and J) is obtained from the reaction between phenylethanoic acid and benzaldehyde by refluxing them in an organic base in the presence of ethanoic anhydride. CH2CO2 H

CHO

+

H

G

(ii)

H

CO2 H C C

+

C C CO2 H

J

Draw a labelled diagram for the assembly of apparatus for refluxing the reaction mixture.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 66


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) Common setup 2 of 2: heat under reflux

4.

by Ricky Tsui

experiment (long question)

[04CE/9(b)/3 marks] (b) An ester can be prepared by heating an alkanol with an alkanoic acid under reflux in the presence of concentrated sulphuric acid. (i)

Draw a labelled diagram to show the set-up used in heating the reaction mixture under reflux.

(ii)

Suggest ONE reason why it is necessary to heat the mixture under reflux.

Heat under reflux can prevent loss of volatile reactants by evaporation.

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 67


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) Common setup 2 of 2: heat under reflux

4.

by Ricky Tsui

experiment (long question)

[09AL/paperI/8(a)(c)/3 marks] 8.

3-Methly-1-butyl ethanoate, commonly known as isoamyl acetate, is a naturally occurring compound having a distinctive pleasant banana odour and is used in food flavouring. In an experiment to prepare the compound, 5.0 cm3 of isoamyl alcohol is allowed to react with 15.0 cm3 of glacial acetic acid in the presence of a reagent L.

(a)

Suggest what reagent L may be and give the reaction conditions for this preparation.

(c) Draw a labelled diagram of the assembly of apparatus used in this preparation.

Common reactions that require heat under reflux: 1. Oxidation of 1o alkanol to alkanoic acid 2. Esterification 3. Substitution reaction (R-OH and H-X) & (R-X and NaOH)

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Page 68


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) 5. Percentage yield =

by Ricky Tsui

percentage yield (%)

actual (experimental) mass of the product obtained theoretical (found by mole ratio) mass of the product obtained

x100%

5 g of ethanoic acid and 5 g of ethanol are mixed and heated in the presence of an acid under reflux for two hours. The resultant mixture was treated to separate the ester ethyl ethnaoate. The mass of ester obtained after distillation is 5.5 g. (Relative atomic masses: C = 12.0, H = 1.0, O = 16.0)

(a) Which reactant is in excess? Show your calculation.

(b) What is the theoretical mass of ethyl ethanoate formed?

(c) What is the percentage yield of ethyl ethanoate?

(a) no. of mole of ethanol used = 5 / (12 x 2 + 1 x 6 + 16) = 0.109 mole no. of mole of ethanoic used = 5 / (12 x 2 + 1 x 4 + 16 x 2) = 0.0833 mole from the equation mole ratio of ethanol : ethanoic acid = 1 : 1 ethanol is in excess (b) 0.0833 x (12 x 4 + 1 x 4 + 16 x 2) = 7.33 g (c) Percentage yield of ethyl ethanoate = (5.5 / 7.33) x 100 % = 75.0 %

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A) 5.

by Ricky Tsui

percentage yield (%)

In an experiment to prepare 2-chloro-2-methylpropane, a mixture of 30 g of (CH3)3COH and 43.2 g of HCl was heated under reflux for 30 minutes to give 33.6 g of (CH 3)3CCl. (Relative atomic masses: H = 1, C = 12, O = 16, Cl = 35.5) (a) Name the type of the reaction. (b) Find the limiting reactant of the reaction.

(c) Calculate the percentage yield of (CH3)3CCl.

substitution, HCl in excess, 89.6 %

[08AL/paperII/5(a)(ii)(I)/2 marks]

a special one - percentage yield (%)

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Page 71


Topic XI – Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

n = number of C atoms Homologous series

General structure

General formula

Function group

Alkanes

CnH2n+2

Nil

Alkenes

CnH2n (n  2)

Haloalkanes

CnH2n+1X

R-X

C=C double

- Cl halogen - OH hydroxyl

Alkanols

CnH2n+1OH

Aldehydes

RCHO

Ketones

RCOR’

Alkanoic acids

CnH2n+1COOH

Esters

RCOOR’

R-OCO-R’ ester

RCONH2

- NH2 amine

Amides (unsubstituted) Amine (primary)

RNH2

bond

group

- CO carbonyl

group / aldehyde group - CO carbonyl group / ketone group - COOH

- NH2

carboxyl group group

group

amine group

(where R or R’ are the alkyl groups, X is the halogen atom)

Properties of members in the SAME homologous series: 1. have same 2. show a

general formula

gradual change in physical properties

(e.g. solubility in water, boiling point and melting point, etc.) 3. show similar

chemical properties

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

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Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

www.hksciblog.edublogs.org/dse-chem

Page 73


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

www.hksciblog.edublogs.org/dse-chem

Page 74


Topic XI â&#x20AC;&#x201C; Chemistry of Carbon Compounds (Part A)

by Ricky Tsui

Ch46 Typical reactions of organic compounds / Ch47 Inter-conversions of carbon compounds

www.hksciblog.edublogs.org/dse-chem

Page 75

Topic 11 chemistry of carbon compounds (parta)  
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