ScoreChem962/3_set 5

ScoreChem 962/3

Set 5 (08)

SECTION A

1. What is the product when propene is oxidised with cold dilute potassium manganate(VII)?

A CH3CH(OH)CH2OH

B CH3CH2CH2OH

C CH3CH2CHO

D CH3COCH3

2. The structural formula of a compound is as follows.

CH3C = CHCH2CHCH2CHO | | CH3 CH3

 What is its IUPAC name?

A 2,5-dimetylhept-2-enal

B 3,6-dimetylhept-2-enal

C 2,5-dimetylhept-5-enal

D 3,6-dimetylhept-5-enal

3. How many total alkenes (including stereoisomers) are possible for the product of the following reaction? heatCH3 CH(CH3) CHBr CH2CH2CH3 ALKENES

alcoholic KOH

A 2 B 3C 4 D 5

4. Which of the following species can act as a nucleophile?

A CH3 B Br+

C AlCl3 D CN-

5. Which of the following reagent is used to distinguish phenol from phenylmethanol?

A Ethanoyl chloride

B Chloroethane

C Bromine water

D Iodine solution

6. Which pair of reagents cannot be used to prepare CH3CH2Cl?

A CH2 = CHCl + H2

B CH3CH2OH + HCl

C CH3CH2OH + Cl2

D CH3CH2NH2 + Cl2

7. Z , with a formula of

gives an orange precipitate with 2,4-DNPH reagent, no precipitate with Fehling’s solution and no reaction with phosphorous pentachloride. It contains a chiral carbon atom. The C4H7O group in the molecule Z could be

HO

C4H7O

A CH2 = C – CH(OH)CH3

|

O = C – CH(CH3) CH3

|CH3 – CH CO CH3

|CH3 – C(CH3) CHO |

B

C D

8. Which of the following compounds reacts easily with cold water?

Cl CH2Cl CH3CH2 Cl

CH3CH2 COCl

A B C

D

9. What is the principal product from the following series of reactions?

LiAlH4 PBr3 KCN LiAlH4

Ether Alcohol Ether Ether heat

COOH

CH2NH

2

CH2 CH2 NH2 CH2CONH

2

CH2CH(OH)NH2

A

C

B

D

10. Which of the following is not true

for proteins?

A They are natural condensation

polymers

B They are built up from identical

monomer units

C They are able to be hydrolysed

D They are built up from amino

acids

11. Adrenaline has the following formula

Which of the following statements about adrenaline is correct?

A It is a primary amineB It is chiral and contains three alcohol groupsC It is chiral and contains two phenol groupsD It exhibits cis-trans isomerism

HO

CH(OH)CH2NHCH3H

O

12. Nylon-6,6 can be made by condensation polymerisation of a compound X and hexane-1,6-diamine.

  -(--- N – C – (CH2)4 – C – N – (CH2)6 – N – C ---)- | || || | | || H O O H H O

Compound X could be

A hexane-1,6-diolB hexanedioyl chlorideC potassium hexanedioateD hexanoic acid

13. The principle product formed when hydrogen iodide reacts with prop-1-ene is 2-iodopropane rather than 1-iodopropane. Which of the following statements is correct regarding this observation?

A Production of 2-iodopropane proceeds at a higher rate than that leading to the production of 1-iodopropane

B Production of 2-iodopropane proceeds via a primary carbonium

C Production of 2-iodopropane proceeds via a secondary carbonium

D 2-iodopropane is more stable than 1-iodopropane

14.The organic compounds which are expected to decolourise bromine water include

I CH3CH = CH COOH

II CH3CH(OH) CH2CH3

III C6H5 – OH

A I and II B I and III C II and III D I, II and III

15.Which of the following statements suggests the presence of free radicals in the bromination of methylbenzene?

I The reaction proceeds most quickly in sunlight

II Hydrogen bromide is present in the product

III Bromomethylbenzene is formed as the first product

A I only B I and II C I and III D II and III

1. What is the product when propene is oxidised with cold dilute potassium manganate(VII)?

A CH3CH(OH)CH2OH

B CH3CH2CH2OH

C CH3CH2CHO

D CH3COCH3

2. The structural formula of a compound is as follows.

CH3C = CHCH2CHCH2CHO | | CH3 CH3

 What is its IUPAC name?

A 2,5-dimetylhept-2-enal

B 3,6-dimetylhept-2-enal

C 2,5-dimetylhept-5-enal

D 3,6-dimetylhept-5-enal

3. How many total alkenes (including stereoisomers) are possible for the product of the following reaction? heatCH3 CH(CH3) CHBr CH2CH2CH3 ALKENES

alcoholic KOH

A 2 B 3

C 4 D 5

4. Which of the following species can act as a nucleophile?

A CH3 B Br+

C AlCl3 D CN-

5. Which of the following reagent is used to distinguish phenol from phenylmethanol?

A Ethanoyl chloride

B Chloroethane

C Bromine water

D Iodine solution

6. Which pair of reagents cannot be used to prepare CH3CH2Cl?

A CH2 = CHCl + H2

B CH3CH2OH + HCl

C CH3CH2OH + Cl2

D CH3CH2NH2 + Cl2

7. Z , with a formula of

gives an orange precipitate with 2,4-DNPH reagent, no precipitate with Fehling’s solution and no reaction with phosphorous pentachloride. It contains a chiral carbon atom. The C4H7O group in the molecule Z could be

HO

C4H7O

A CH2 = C – CH(OH)CH3

|

O = C – CH(CH3) CH3

|CH3 – CH CO CH3

|CH3 – C(CH3) CHO |

B

C D

8. Which of the following compounds reacts easily with cold water?

Cl CH2Cl CH3CH2 Cl

CH3CH2 COCl

A B C

D

9. What is the principal product from the following series of reactions?

LiAlH4 PBr3 KCN LiAlH4

Ether Alcohol Ether Ether heat

COOH

CH2NH

2

CH2 CH2 NH2 CH2CONH

2

CH2CH(OH)NH2

A

C

B

D

10. Which of the following is not true

for proteins?

A They are natural condensation

polymers

B They are built up from identical

monomer units

C They are able to be hydrolysed

D They are built up from amino

acids

11. Adrenaline has the following formula

Which of the following statements about adrenaline is correct?

A It is a primary amineB It is chiral and contains three alcohol groupsC It is chiral and contains two phenol groupsD It exhibits cis-trans isomerism

HO

CH(OH)CH2NHCH3H

O

12. Nylon-6,6 can be made by condensation polymerisation of a compound X and hexane-1,6-diamine.

  -(--- N – C – (CH2)4 – C – N – (CH2)6 – N – C ---)- | || || | | || H O O H H O

Compound X could be

A hexane-1,6-diol

B hexanedioyl chloride

C potassium hexanedioateD hexanoic acid

13. The principle product formed when hydrogen iodide reacts with prop-1-ene is 2-iodopropane rather than 1-iodopropane. Which of the following statements is correct regarding this observation?

A Production of 2-iodopropane proceeds at a higher rate than that leading to the production of 1-iodopropane

B Production of 2-iodopropane proceeds via a primary carbonium

C Production of 2-iodopropane proceeds via a secondary carbonium

D 2-iodopropane is more stable than 1-iodopropane

14.The organic compounds which are expected to decolourise bromine water include

I CH3CH = CH COOH

II CH3CH(OH) CH2CH3

III C6H5 – OH

A I and II B I and III C II and III D I, II and III

15.Which of the following statements suggests the presence of free radicals in the bromination of methylbenzene?

I The reaction proceeds most quickly in sunlight

II Hydrogen bromide is present in the product

III Bromomethylbenzene is formed as the first product

A I only B I and II C I and III D II and III

SECTION BARE YOU READY??

Q16 [8 marks]

(a) Paracetamol and aspirin have analgesic (pain killing) action and are readily absorbed from the intestines.

CH3CONH OH

COOH

O – C – CH3

O

Paracetamol

Aspirin

Each drug is easily hydrolysed by enzymes in the intestine. For each drug, name the group which is hydrolysed. [2 marks]

(b) Adrenalin is a hormone which, when secreted directly into the bloodstream, acts as a stimulant. It has the structure as below.

HO

HO

CH – CH2 – NHCH3OH

(i) Name three functional groups present in the adrenalin molecule. [3 marks] (ii) By means of asterisk, identify the chiral centre in the structure of adrenalin drawn above.

[1 mark]

Q16

HO

HO

CH – CH2 – NHCH3OH Adrenalin

(iii) The synthesis of adrenalin includes the following stages:

HO

HO

CHO

A B Adrenalin

Give the full structure formulae of A and B. [2 marks]

Q16

HCN H2, Ni

Q17 [7 marks](a) H2N – CH(CH3)COOH H2N – CH2COOH Alanine Glycine

  (i) Name the functional groups present in the amino acids given above.

[2 marks](ii) Draw the structure of the

zwitterions for alanine.[1 mark]

   (iii) Write a reaction equation to show what would happen when alanine dissolves in hydrochloric acid.

[1 mark]   (iv) Draw one structural formula for the dipeptide formed between alanine and glycine.

[1 mark]

Q17(b) The synthetic rubber SBR is a copolymer of styrene (phenylethene) and buta-1,3-diene in the ratio of 3 : 1.

(i) Draw the structure of SBR. [1 mark]

  (ii) What is the type of polymerisation used to produce SBR?

[1 mark]

Q16

A B

HO

HO

CHCN

OH

(a) Paracetamol = amide, aspirin = ester

(b)(i) Phenol, Hydroxy, Amino

(ii) – *CH(OH) – CH2 – NHCH3

(iii)

HO

HO

CHCH2NH2OH

(a) 1 amino group

2 carboxyl group

3 +H3N – CH(CH3) COO –

4 H2N-CH(CH3)COOH + HCl

ClH3N- CH(CH3)COOH

5 H2N – CH(CH3) – CONH – CH2COOH

OR H2N – CH2 – CONH – CH(CH3)COOH6 [peptide link] C – N

|| | O H

(b)1 --(-- CH – CH --)3-(-- CH2CH = CHCH2 --)--

2 addition polymerization

Q17

SECTION CARE YOU REALLY READY??

Q18An organic compound, Z, has the following composition by mass:

C, 62.1% H, 10.3% O, 27.6%

(a) Determine the empirical formula of Z. [3 marks]

(b) Z has three isomers, E, F and G. E is an alcohol, F is a ketone and G is an aldehyde. Draw possible structural formulae for E, F and G.

[3 marks]

Q18(c) Describe tests that would allow you to show that:

(i) E is an alcohol, whereas F and G are not,

[3 marks]

  (ii) F and G are carbonyl compounds, whereas E is not,

[3 marks]

  (iii) G is aldehyde, whereas E and F are not. [3 marks]

Q19(a)

Dopamine

(i) Draw a structure of the product formed when dopamine reacts with warm dilute nitric acid.

[1 mark]

  (ii) Explain any type of reaction which takes place.

[4 marks]

HO

CH2CH2NH2

HO

(b) Dopamine can be synthesised from the following compound.

Outline a scheme of reactions illustrates the synthesis of dopamine. State reagents and conditions required. [5 marks]

HO

CH3

HO

(c) Compounds R and S are two isomers with molecular formula C8H10O. R gives off white fumes with thionyl chloride and forms a yellow precipitate with alkaline aqueous iodine but S does not. S dissolves in aqueous potassium hydroxide but R does not.

Explain the above observations and write the structural formulae of R and S.

[5 marks]

C

(a)

Element C H O

1 moles of 62.1/12.0 10.3 /1.0 27.6

/16.0

2 Ratio 3 6 1

3 empirical formula C3H6O

(b)

1 E CH2 = CH CH2OH OR CH2

= C(OH) CH3

2 F CH3 CO CH3

3 G CH3CH2CHO

Q18

(C) [9 marks]

1,2 [E=alcohol] PCl5 r.t. / Na, r.t.

3 white fumes, HCl / effervescence occurs, H2

 4,5 [F, G=carbonyl]

2,4-dinitrophenylhydrazine, heat

6 orange ppt

 7,8 [G=aldehyde] Tollen’s reagent, heat

/ Fehling solution, heat

9 silver mirror / reddish brown ppt formed

Q18

Q19

1

2 acid – base reaction / neutralisation

3 NH2 (amino) group is basic due to the lone

pair electrons on N

4 electrophilic substitutions

5 OH (phenol) group activates the benzene

ring / benzene ring is richer in electron

density

/ lone pair electrons from O delocalized

into

benzene ring

HO

CH2CH2NH3+

HO

NO2

NO2O2N

Q19

(b) [5 marks]

1 Cl2, UV

2 [product] - CH2Cl

3 KCN / alcohol, reflux

4 [product] - CH2CN

5 H2, Ni, 180C /

LiAlH4 in dry ether followed by acidic

hydrolysis

(c) [5 marks]

1 [R gives off white fumes with SOCl2]

R has OH group / R is an alcohol

2 [R forms yellow ppt with I2/NaOH]

R has a structure of – CH(CH3)OH

3 [S dissolves in KOH]

S is acidic / S is a phenol

4 R is C6H5 – CH(OH)CH3

5 S is HO – C6H4 – CH2CH3or

HO – C6H3 – (CH3)2

Q19

Sigh! Why didn’t I study hard from the beginning??

YES!! I GOT IT.