Chemistry (2)

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CHEMISTRY Bertujuan membantu calon STPM yang gagal atau berprestasi lulus sebahagian ke arah meningkatkan pencapaian agar mencapai tahap LULUS PENUH

Transcript of Chemistry (2)

Page 1: Chemistry (2)

CHEMISTRY

Bertujuan membantu calon STPM yang gagal atau berprestasi lulus sebahagian ke arah meningkatkan pencapaian agar mencapai tahap LULUS PENUH

Digubal oleh tenaga pengajar STPM berpengalaman di Johor Darul Takzim

Page 2: Chemistry (2)

PANEL PENGGUBAL:

1. EN. TAN KIM TA

SMK TINGGI, BATU PAHAT

2. PN. HO NIAK OIE

SMK DATO’ PENGGAWA BARAT, PONTIAN

3. PN. TEH FUI LING

SMK LEDANG, MUAR

4. CIK LEE MING ENG

SMK TINGGI, SEGAMAT

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CONTENTS

Title Page

1. ROUTES FOR SYNTHESIS OF ORGANIC COMPOUNDS 3 - 11

2. ASSESSMENT EXERCISE A 12 - 13

3. ANSWERS FOR ASSESSMENT EXERCISE A 14 - 15

4. DIAGNOSTIC EXERCISE A 16 – 17

5. ANSWERS FOR DIAGNOSTIC EXERCISE A 18 - 20

6. ASSESSMENT EXERCISE B 21

7. ANSWERS FOR ASSESSMENT EXERCISE B 22 - 23

8. DIAGNOSTIC EXERCISE B 24

9. ANSWERS FOR DIAGNOSTIC EXERCISE B 25 - 26

10. ASSESSMENT EXERCISE C 27 - 29

11. ANSWERS FOR ASSESSMENT EXERCISE C 30 - 34

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ALKENES

BENZENES

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METHYLBENZENES

ALCOHOLS

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HALOALKANES

PHENOLS

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ALDEHYDES

KETONES

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BENZALDEHYDES

CARBOXYLIC ACIDS

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BENZOIC ACIDS

ESTERS

AMINES

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PHENYLAMINE

AMINO ACIDS

GRIDNARD REAGENTS

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ACYL CHLORIDES

SAYTZEFF’S RULE

When the dehydration of an alcohol produces a mixture of alkenes, the identity of the

major product obtained may be predicted by Saytzeff’s rule. This states that the

alkene containing the greater number of alkyl substituents is the predominant

product.

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NOTE 2

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MARKOVNIKOFF’S RULE

States that the more electronegative atom (the chlorine atom of HCl) becomes

more attached to the carbon atom (of the unsymmetrical alkene) containing fewer

hydrogen atoms. The rule applies to the addition of water, sulphuric acid, chloric (I)

acid (HOCl) and bromic (I) acid (HOBr) as well as to the addition of hydrogen halides

to unsymmetrical alkenes.

The test for the functional group

Functional group Chemical test / observations

1

C=C

Reagent: Bromine in CCl4

Condition : Room temperature

Decolourisation of bromine occurs immediately

CH2=CH2 + Br2 CH2BrCH2Br

2

R—OH

(i)Reagent : PCl5

Condition : Room temperature

White fumes of HCl liberated

ROH + PCl5 RCl + POCl3 + HCl (g) or

RCOOH + PCl5 RCOCl + POCl3 + HCl (g)

(i) Reagent : Na

Condition : Room temperature

Hydrogen gas liberated

2ROH + 2Na 2RONa + H2 (g) or

2RCOOH + 2Na 2RCOONa + H2 (g)

3 O

C

Reagent : 2,4-dinitrophenylhydrazine

Condition : Room temperature

Yellow / orange precipitate formed

O2N

C=O + H2NNH— NO2

O2N

C= NNH NO2 + H2O(l)

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4 O

C—OH

Reagent :Na2CO3(aq)

Condition : room temperature

Carbon dioxidegas liberated

2RCOOH+Na2CO3(aq)2RCOONa+ CO2(g) H2O(l)

5 Phenol or phenylamine

OH

NH2

Reagent : Bromine water

Condition : room temperature

White precipitated of 2,4,6-tribromophenol or

(2,4,6-tribromophenylamine ) formed.

Decolourisation of bromine water

OH Br OH Br

+ 3Br2 (aq) + 3HBr

Br

Assessment Exercise A

1. Give the equation, the conditions needed and the names of the products when

(a) but-2-ene reacts with hydrogen bromide

(b) propene reacts with bromine in tetrachloromethane

(c) cyclohexene reacts with hydrogen

(d) propene reacts with concentrated sulphuric (VI) acid

2. Write the structural formula formed in the following reactions.

(a) + CH3CH2Br in the presence of FeBr3

(b) + COCl in the presence of AlCl3

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(c) + HNO3/H2SO4 at 50oC

(d) + Cl2 in the presence of iron catalyst

3. Suggest the reagents and conditions necessary to convert CH3CH2Br into

(a) CH3CH2NH2

(b) CH3CH2OH

(c) CH2 = CH2

(d) CH3CH2MgBr

4. Draw the structures of the product when methylmagnesium bromide, CH3MgBr in dry ether reacts with the following compounds followed by hydrolysis with dilute acid.

(a) methanal, HCHO

(b) CH3CHO

(c) CH3COCH3

(d) CO2

5. Draw the structures of the products of the following reactions.

(a) oxidation of 2-methylpropan-1-ol

(b) butan-2-ol with PCl5

(c) propan-1-ol reflux with ethanoic acid in the presence of concentrated

sulphuric (VI) acid

(d) heating cyclohexanol with concentrated phosphorus (V) acid

6. Give the equation for the reaction between phenol, OH with

(a) sodium metal

(b) sodium hydroxide

(c) ethanoyl chloride, CH3COCl

(d) bromine water

7. Give the reagents, conditions and the equations for the following conversions.

(a) Ethanal, CH3CHO → ethanal cyanohydrin, CH3CH(OH)CN

(b) Propanal, CH3CH2CHO → propanal oxime, CH3CH2CH=N–OH

(c) Propanone, CH3COCH3 → propanone phenylhydrazone

(d) Ethanal, CH3CHO → ethanal 2,4-dinitropheylhydrazone

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8. Write equations to show the reactions occurring between

(a) ethanoic acid, CH3COOH and phosphorus (III) chloride, PCl3

(b) propanoic acid, CH3CH2COOH and lithium tetrahydridoaliminate (III)

(c) methanoic acid and hydrogen gas over heated nickel

(d) heating sodium ethanoate and soda lime

9. Suggest the reagents and conditions for the following conversions.

(a) Methylamine, CH3NH2 → methanol, CH3OH

(b) Ethylamine, CH3CH2NH2 → N-ethylethanamide, CH3CONHCH2CH3

(c) Ethylamine, CH3CH2NH2 → diethylamine, (CH3CH2)2NH

(d) Phenylamine, NH2 → 2,4,6-tribromophenylamine

10. State the observations for the following reactions.

(a) Ethanol reacts with phosphorus (V) chloride

(b) Propene reacts with bromine in tetrachloromethane

(c) Butan-2-ol reacts with alkaline iodine

(d) propanal reacts with ammoniacal silver nitrate solution

(e) propanone with 2,4-dinitrophenylhydrazine

Answers (Assessment Exercise A)

Equation Conditions Name of product

1(a) CH3CH=CHCH3 + HBr → CH3CH2CHBrCH3 Room temperature 2-bromobutane

(b) CH3CH=CH2 + Br2 → CH3CHBrCH2Br Room temperature 1,2-dibromopropane

(c) + H2 → Ni catalyst, 150oC cyclohexane

(d) CH3CH=CH2 + H2SO4 → CH3CH(OSO3H)CH3 cold 2-propyl- hydrogensulphate

2(a)

(b)

(c) (d) CH2CH3

NO2 Cl

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C ıı O

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Reagents Conditions

3(a) Concentrated ammonia in ethanol in a sealed tube Room temperature

(b) Dilute NaOH(KOH) in ethanol Reflux

(c) KOH dissolved in ethanol Reflux

(d) Magnesium turning Dry ethoxyethane (ether)

4(a) CH3CH2OH

(b) CH3CH(OH)CH3

(c) (CH3)2C(OH)CH3

(d) CH3COOH

5(a) (CH3)2CHCOOH

(b) CH3CH2CH(Cl)CH3

(c) CH3COOCH2CH2CH3

(d)

Equation

6(a) 2 OH + 2Na →2 ONa + H2

(b) OH + NaOH → ONa + H2O

(c) OH + CH3COCl → CH3COO + HCl

(d)

OH

Br

Br

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OH + 3Br2 → Br + 3HBr

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Reagents Conditions Equation

7(a) KCN , dilute H2SO4 10 – 20oC CH3CHO + HCN → CH3CH(OH)CN

(b) Hydroxylamine Warm CH3CH2CHO + H2NOH → CH3CH2CHNOH + H2O

(c) Phenylhydrazine Room temperature

CH3COCH3 + C6H5NHNH2 → (CH3)2C=N-NHC6H5 + H2O

(d) 2,4-dinitrophenylhydrazine Room temperature

CH3CHO + 2,4-DNPH → CH3CH-(2,4-DNPH) + H2O

Equation

8(a) 3CH3COOH + PCl3 → 3CH3COCl + H3PO3

(b) CH3CH2COOH + 4[H] → CH3CH2CH2OH + H2O

(c) HCOOH + 3H2 → CH4 + 2H2O

(d) CH3COONa + NaOH → CH4 + Na2CO3

Reagents Conditions

9(a) NaNO2 , dilute HCl Room temperature

(b) CH3COCl Room temperature

(c) CH3CH2I in ethanol Heat in a sealed tube

(d) Bromine water Room temperature

Observations

10(a) White fume of hydrogen chloride formed.

(b) Brown colour of bromine decolourised.

(c) Yellow solid (triiodomethane) formed.

(d) Silver mirror formed on the wall of the test tube.

(e) Yellow crystalline solid formed.

Diagnostic Exercise A

1. Give the equation, the conditions needed and the names of the products when

(a) pent -2-ene reacts with hydrogen bromide

(b) ethene reacts with bromine in tetrachloromethane

(c) 4-methyl-cyclohexene reacts with hydrogen

(d) but-1-ene reacts with concentrated sulphuric (VI) acid

2. Write the structural formula formed in the following reactions.

(a) + CH3Br in the presence of FeBr3

(b) + CH3COCl in the presence of AlCl3

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(c) + concentrated HNO3 with concentrated H2SO4 catalyst at 50oC

(d) + Br2 in the presence of iron catalyst

3. Suggest the reagents and conditions necessary to convert CH3CH2CH2Br into

(a) CH3CH2 CH2NH2

(b) CH3 CH2CH2OH

(c) CH3CHCH2

(d) CH3CH2CH2MgBr

4. Draw the structures of the product when methylmagnesium bromide, C2H5MgBr in dry ether reacts with the following compounds followed by hydrolysis with dilute acid.

(a) methanal, HCHO

(b) CH3CHO

(c) CH3COCH3

(d) CO2

5. Draw the structures of the products of the following reactions.

(a) oxidation of 2-methylbutan-1-ol

(b) pentan-2-ol with PCl5

(c) butan-1-ol reflux with ethanoic acid in the presence of concentrated

sulphuric (VI) acid

(d) heating 2-methylcyclohexanol with concentrated phosphorus (V) acid

6. Give the equation for the reaction between 4-methylphenol with

(a) sodium metal

(b) sodium hydroxide

(c) ethanoyl chloride, CH3COCl

(d) bromine water

7. Give the reagents, conditions and the equations for the following conversions.

(a) Propanal, C2H5CHO → propanal cyanohydrin, C2H5CH(OH)CN

(b) Ethanal, CH3CHO → ethanal oxime, CH3CH=N–OH

(c) Butanone, C2H5COCH3 → butanone phenylhydrazone

(d) Butanal, C3H7CHO → butanal 2,4-dinitropheylhydrazone

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8. Write equations to show the reactions occurring between

(a) propanoic acid, C2H5COOH and phosphorus (III) chloride, PCl3

(b) ethanoic acid, CH3COOH and lithium tetrahydridoaliminate (III)

(c) butanoic acid, C3H7COOH and hydrogen gas over heated nickel

(d) heating sodium propanoate, C2H5COONa and soda lime

9. Suggest the reagents and conditions for the following conversions.

(a) Ethylamine, C2H5NH2 → ethanol, C2H5OH

(b) Methylamine, CH3NH2 → N-methylethanamide, CH3CONHCH3

(c) Methylamine, CH3NH2 → dimethylamine, (CH3)2NH

10. State the observations for the following reactions.

(a) Propanol reacts with phosphorus (V) chloride

(b) Ethene reacts with bromine in tetrachloromethane

(c) Pentan-2-ol reacts with alkaline iodine

(d) Ethanal reacts with ammoniacal silver nitrate solution

(e) Butanone with 2,4-dinitrophenylhydrazine

Answers (Diagnostic Exercise A)

Equation Conditions Name of product

1(a) C2H5CH=CHCH3 + HBr → C2H5CH2CHBrCH3 Room temperature 2-bromopentane

(b) CH2=CH2 + Br2 → CH3CHBrCH2Br Room temperature 1,2-dibromoethane

(c) Ni catalyst, 150oC methylcyclohexane

(d) C2H5CH=CH2 + H2SO4 → C2H5CH(OSO3H)CH3 cold 2-butyl hydrogensulphate

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CH3 + H2 CH3

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2(a)

(b)

(c) (d)

Reagents Conditions

3(a) Concentrated ammonia in ethanol in a sealed tube Room temperature

(b) Dilute NaOH(KOH) in ethanol Reflux

(c) KOH dissolved in ethanol Reflux

(d) Magnesium turning Dry ethoxyethane (ether)

4(a) C2H5CH2OH

(b) CH3CH(OH)C2H5

(c) (CH3)2C(OH)C2H5

(d) C2H5COOH

5(a) CH3CH2CH(CH3)COOH

(b) CH3CH2CH2CH(Cl)CH3

(c) CH3COOCH2CH2CH2CH3

(d)

CH3

Equation

6(a)

(b)

CH3

NO2 Br

OH

CH3

ONa

CH3

OH

CH3

ONa

CH3

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C-CH3 ıı O

2 + 2Na → 2 + H2

+ NaOH → + H2O

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(c)

(d)

Reagents Conditions Equation

7(a) KCN , dilute H2SO4 10 – 20oC C2H5CHO + HCN → C2H5CH(OH)CN

(b) Hydroxylamine Warm CH3CHO + H2NOH → CH3CHNOH

(c) Phenylhydrazine Room temperature

C2H5COCH3 + C6H5NHNH2 → C2H5(CH3)C=N-NHC6H5

(d) 2,4-dinitrophenylhydrazine Room temperature

C3H7CHO + 2,4-DNPH → C3H7CH-(2,4-DNPH)

Equation

8(a) 3C2H5COOH + PCl3 → 3C2H5COCl + H3PO3

(b) CH3COOH + 4[H] → CH3CH2OH + H2O

(c) C3H7COOH + 3H2 → C4H10 + 2H2O

(d) C2H5COONa + NaOH → C2H6 + Na2CO3

Reagents Conditions

9(a) NaNO2 , dilute HCl Room temperature

(b) CH3COCl Room temperature

(c) CH3CH2I in ethanol Heat in a sealed tube

Observations

10(a) White fume of hydrogen chloride formed.

(b) Brown colour of bromine decolourised.

(c) Yellow solid (triiodomethane) formed.

(d) Silver mirror formed on the wall of the test tube.

OH

CH3

OOCCH3

CH3

OH

CH3

OH

Br

CH3

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+ Br2 → Br

+ CH3COCl →

+ 2HBr

+ HCl

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(e) Yellow crystalline solid formed.

ASSESSMENT EXERCISE B

1. Give the reagents and conditions for the following sequence of reactions.

(a) CH3 COOH COCl

(b) CH2 = CHCH3 CH3CHBrCH3 CH3CHOHCH3

(c) CH3 COOH

(d) CH3Br CH3CN CH3COOH

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(e) CH3CH2Br CH3CH2CN CH3CH2CH2NH2

(f) BrCH2CH2Br NCCH2CH2CN HOOCCH2CH2COOH

(g) CH2I CH2OH CH2OOCCH3

(h) NO2 NH2 NHCOCH3

(i) C2H5Br C2H5 MgBr C2H5C(OH)(CH3)2

2. Write the reaction scheme to show how you would carry out the following

conversions, by stating the reagents and conditions.

(a) CH2 = CH2 CH2 CH2NH2

(b) CH3CH2Br CH3CHO

(c) CH3CH2Cl CH3CH2COOH

(d) CH3CH2OH HOCH2CH2OH

(e) CH3CHOH BrCH2CH2Br

(f) Br CH2OH

(g) NO2 NHCO

(h) CH3I (CH3)2CHOH

(i) BrCH2CH2Br H2NCH2CH2CH2CH2NH2

ANSWERS FOR ASSESSMENT EXERCISE B

No. 1

(a) KMnO4/ H+, reflux ; PCl5, room temperature,

(b) HBr gas, room temperature ; aqueous NaOH, reflux

(c) CH3I / AlCl3 , room temp. ; KMnO4/ H+, reflux

(d) KCN / ethanol, reflux ; dil. H2SO4, reflux

(e) KCN / ethanol, reflux ; H2 / nickel , 1800C

(f) KCN / ethanol, reflux ; dil. H2SO4, reflux

(g) aqueous NaOH, reflux ; CH3COOH, conc H2SO4, reflux

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(h) Sn / conc HCl, room temp. ; CH3COCl, room temp.

(i) Mg / ether, room temp. ; propanone / H3O+

No. 2

(a) CH2 = CH2 CH3CH2Br CH3CH2NH2

Step I : HBr gas , room temp

Step II : conc NH3 / ethanol , heat

(b) CH3CH2Br CH3CH2OH CH3CHO

Step I : aq NaOH, reflux

Step II : KMnO4 / H+ , heat

(c) CH3CH2Cl CH3CH2CN CH3CH2COOH

Step I : aq KCN / ethanol, reflux

Step II : dil H2SO4 , reflux

(d) CH3CH2OH CH2=CH2 HOCH2CH2OH

Step I : conc H2SO4, 180oC

Step II : KMnO4, room temp.

(e) CH3CH2OH CH2=CH2 BrCH3CH2Br

Step I : conc H2SO4 , 180 oC

Step II : Br2 /CCl4 , room temp.

(f) Br MgBr CH2OH

Step I : Mg / ether

Step II : methanal / H3O+

(g) NO2 NH2 NHCO

Step I : Sn / conc HCl , room temp.

Step II : COCl, room temp.

(h) CH3I CH3MgBr (CH3)2CHOH

Step I : Mg / ether

Step II : CH3CHO / H3O+

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(i) BrCH2CH2 Br NCCH2CH2CN H2NCH2CH2CH2CH2NH2

Step I : aq KCN / ethanol, reflux

Step II : H2 / nickel, 180 oC

DIAGNOSTIC EXERCISE B

1. Give the reagents and conditions for the following sequence of reactions.

(a) CH2CH3 COOH COCl

(b) CH3CH = CHCH3 CH3CH2CHBrCH3 CH3CH2CHOHCH3

(c) CH3 CH3 CH3 HOOC COOH

(d) CH3CH2Br CH3CH2CN CH3 CH2COOH

(e) CH3Br CH3CN CH3CH2NH2

(f) BrCH2CH2CH2Br NCCH2CH2CH2CN HOOCCH2CH2CH2COOH

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(g) CH2Br CH2OH CH2OOCCH3

(h) NO2 NH2 NHCOCH2CH3

(i) C2H5Br C2H5 MgBr C2H5CH(OH)(CH3)

2. Write the reaction scheme to show how you would carry out the following

conversions, by stating the reagents and conditions. The conversion may

involve more than one step.

(a) CH2 = CH2 CH3CH2CH2NH2

(b) CH3CH2Br CH3COOH

(c) CH3CH2Br CH3CH2COOH

(d) CH3CH2CH2OH CH3CHBrCH3

(e) CH3CH2Br CH3CH2OOCCH3

(f) HOOC COOH

(g) O2N NO2 H3CCOHN NHCOCH3

(h) CH3Br (CH3)2CHOH

(i) CH2CH2 I H2NCH2CH2CH2CH2NH2

ANSWERS FOR DIAGNOSTIC EXERCISE B

1 (a) KMnO4/ H+, reflux ; PCl5, room temperature,

(b) HBr, room temperature ; aqueous NaOH, reflux

(c) CH3I / AlCl3 , room temp. ; KMnO4/ H+, reflux

(d) KCN / ethanol, reflux ; dil. H2SO4, reflux

(e) KCN / ethanol, reflux ; H2 / nickel , 1800C

(f) KCN / ethanol, reflux ; dil. H2SO4, reflux

(g) aqueous NaOH, reflux ; CH3COOH, conc H2SO4, reflux

(h) Sn / conc HCl, room temp. ; CH3CH2COCl, room temp.

(i) Mg / ether, room temp. ; CH3CHO / H3O+

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2 (a) CH2 = CH2 CH3CH2Br CH3CH2CN CH3CH2CH2NH2

Step I : HBr, room temp

Step II : KCN / ethanol, reflux

Step III : H2 / nickel , 1800C

(b) CH3CH2Br CH3CH2OH CH3COOH

Step I : aq NaOH, reflux

Step II : KMnO4 / H+ , reflux

(c) CH3CH2Br CH3CH2CN CH3CH2COOH

Step I : aq KCN / ethanol, reflux

Step II : dil H2SO4 , reflux

(d) CH3CH2CH2OH CH3CH=CH2 CH3CHBrCH3

Step I : conc H2SO4, 180oC

Step II : HBr, room temp.

(e) CH3CH2Br CH3CH2OH CH3CH2OOCCH3

Step I : aq NaOH, reflux

Step II : CH3COOH, conc H2SO4 , reflux

(f) CH3 H3C CH3 HOOC COOH

Step I : CH3Br / AlCl3 , room temp.

Step II : CH3Br / AlCl3 , room temp.

Step III : KMnO4 / H+ , reflux

(g) O2N NO2 H2N NH2 H3CCOHN NHCOCH3

Step I : Sn / conc HCl , room temp.

Step II : CH3COCl, room temp.

(h) CH3Br CH3MgBr (CH3)2CHOH

Step I : Mg / ether

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Step II : CH3CHO / H3O+

(i) CH3CH2 I CH2 = CH2 CH2BrCH2Br CH2CNCH2CN

H2NCH2CH2CH2CH2NH2

Step I : NaOH / ethanol, reflux

Step II : Br2 / room temp

Step III : aq KCN / ethanol, reflux

Step IV : H2 / nickel, 180 oC

Assessment Exercise C

1. State the reagents and conditions (including the catalyst, if any) for the reactions I to V in the scheme below.

CH3 – CH – CH2 – CH2OH CH3 – CH – CH2 – COOH

CH3 CH3

CH3 – CH – CH2 = CH2 CH3 – CH – CH2 – COOC2H5

CH3 CH3

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CH3 – CH – CH2 – CH3 CH3 – CH – C – CH3

CH3 OH CH3 O

Answers:

Reactions Reagents Conditions

I

II

III

IV

V

2. State the reagents, conditions and chemical equations for the conversions as shown in the following scheme.

Answers:

Reactions Reagents Conditions Equations

A

B

C

D

CH3 CH2Cl CH2OH

CONH2 COO-NH4+ COOH

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V

A B C

D

EF

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E

F

3. Draw the structures of the products for the reactions as shown in the following scheme.

C2H5Br

H H I I

CH=CH – CH2 – C = C – CH2OH

CH3

Compound A

4. (a) A compound A has the structure shown above. Write the formula of the products formed when A is (i) shaken with aqueous bromine (ii) treated with phosporus (V) chloride at room temperature. (iii) boiled under reflux with excess acidified aqueous potassium dichromate (VI)

CH3

I

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Dilute KOH,Reflux

MnO4-/H+,

Reflux

C2H5OH,Conc. H2SO4

RefluxEthanolic NH3 Heat in sealed tube

Ethanolic KCN Reflux

Mg in ether

Ethanolic NaOCH3

Heat

CH3COOAg Warm

NaNO2, dilute HClRoom temperature

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H3C CH2 Compound B

(b) Describe what might be observed and give the structural formulae of the products when compound B reacts with

(i) bromine in inert solvent(ii) cold, acidified dilute potassium manganate (VII)

5. Describe a simple chemical test to distinguish between the following pairs of compounds. State the reagents used, conditions of reactions, and observations. Write equations for the reactions involved.

(a) CH3CHOHCH3 and CH3OH

(b) CH3COCH2CH3 and CH3CH2COCH2CH3

(c) CH2CH3 and

(d) CH2OH and OH

. (e) CH2Cl and Cl

(f) CH3CH2CHO and CH3COCH3

(g) CH3CH2NH2 and CH3CH2CONH2

(h) CH3CH2COOH and CH3COOCH3

Answers: (Assessment Exercise C)

1. Reactions Reagents Conditions

I Acidified KMnO4 Reflux

II Ethanol Reflux with concentrated H2SO4

III KOH in ethanol Reflux

IV Steam Concentrated H3PO4, 330oC, 60 atm

V Acidified KMnO4 Reflux

2 Reactions Reagents Conditions Equations

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A CH3Cl AlCl3

Warm

B Cl2 Ultraviolet light

C Dilute KOH in ethanol

Reflux

DAcidified KMnO4

Reflux

E(NH4)2CO3

Room temperature

F _ Heating

CH3

CH3 CH2Cl

CH2Cl CH2OH

CH2OH COOH

COOH COO-NH4+

COO-NH4+ CONH2

31

+ CH3Cl →

+ Cl2 →

+ HCl

+ HCl

+ KOH → + KCl

+ [O] → + H2O

+ (NH4)2CO3 → + CO2 + H2O2 2

→ + H2O

C2H5OH,Conc. H2SO4

Reflux

Dilute KOH,Reflux

MnO4-/H+,

Reflux

Ethanolic NH3 Heat in sealed tube

Ethanolic KCN Reflux

Mg in ether

Ethanolic NaOCH3

Heat

CH3COOAg Warm

NaNO2, dilute HClRoom temperature

C2H5Br CH3COOC2H5

CH3COOHC2H5OHC2H5NH2

3.

Page 33: Chemistry (2)

4. (a)(i) H H I I

CH - CH – CH2 – C - C – CH2OH

CH3

H H I I

CH=CH – CH2 – C = C – CH2Cl (ii)

CH3

H H (iii) I I

CH=CH – CH2 – C = C – COOH

CH3

(b) (i) CH3

H3C CH2Br

(ii) CH3

H3C CH2OH

32

C2H5CN C2H5MgBr C2H5OCH3

I Br

I Br

I Br

I Br

Br

Br

Br

OH

OH

OH

Page 34: Chemistry (2)

5. (a) Reagent : I2/ NaOH(aq) Condition : Heat / Warm For CH3CH(OH)CH3,pale yellow precipitate of triiodomethane, CHI3, is formed. For CH3OH, no visible reaction.

I2/ NaOH(aq) CH3CH(OH)CH3 CHI3(s) + CH3COO-

(b) Reagent : I2/ NaOH(aq) Condition : Heat / Warm For CH3COCH2CH3 ,pale yellow precipitate of triiodomethane, CHI3, is formed. For CH3CH2COCH2CH3, no visible reaction.

I2/ NaOH(aq) CH3COCH2CH3 CHI3(s) + CH3CH2COO-

(c) Reagent : KMnO4 /H+

Condition : Heat For C6H5CH2CH3 , (i) decolourisation of KMnO4 solution occurs. (ii) white precipitate of benzoic acid , C6H5COOH, is formed.

For C6H6 no visible reaction.

KMnO4 /H+ C6H5CH2CH3 + 6[O] C6C5COOH + CO2(g) + 2H2O(g)

(d) Reagent : Bromine water, Br2(aq) Condition : Room Temperature For C6H5OH , (i) decolourisation of bromine water occurs. (ii) white precipitate of 2,4,6-tribromophenol is formed.

For C6H5CH2OH, no visible reaction. Br

OH + 3Br2(aq) Br—v OH + 3HBr(g) Br

(e) Reagent : AgNO3(aq) / ethanol Condition : Warm For C6H5CH2Cl, white precipitate of AgCl is formed.

33

Page 35: Chemistry (2)

For C6H5Cl, no visible reaction. Ag+(aq) + Cl-(aq) AgCl(s)

(f) (i) Reagent : I2/ NaOH(aq) Condition : Heat / Warm For CH3COCH3 ,pale yellow precipitate of triiodomethane, CHI3, is formed. For CH3CH2CHO, no visible reaction.

I2/ NaOH(aq) CH3COCH3 CHI3(s) + CH3COO-

warm (ii) Reagent : Fehling’s solution / Cu2+(aq) Condition : Heat For CH3CH2CHO, brick red precipitate of Cu2O is formed. For CH3CH2CHO, no visible reaction.

Fehling’s solution CH3CH2CHO + Cu2+(aq) CH3CH2COO- + Cu2O(s) Heat (g) Reagent : NaOH(aq) Condition : Heat For CH3CH2CONH2 , ammonia gas is liberated. For CH3CH2NH2, no visible reaction.

CH3CH2CONH2 + NaOH(aq) CH3CH2COO-Na+ + NH3(g) Heat

(h) Reagent : Na2CO3(aq) Condition : room temperature For CH3CH2COOH , carbon dioxide gas is liberated. For CH3CH2COOCH3, no visible reaction.

2 CH3CH2COOH + Na2CO3(aq) 2CH3CH2COO-Na+ + CO2(g) + H2O(g)

34