216420330 q Trial Chemistry Sem 3 Stpm 2013

TERENGGANU

Name : ………………………………………………….…

Form : ……………………

SUMMATIVE ASSESSMENT THIRD TERM STPM 2013

CHEMISTRY One hour and a half hours

2 SECTION A [ 15 marks ] Four suggested answers labelled A, B, C and D are given for each question. Choose one correct answer.

1

A compound with the molecular formula CH3CH(NH2)COOH exists in two shapes. What is it called? A B C D

2

Isotopes. Cis – trans isomers. Optical isomers. Structural isomers.

What reagent is used to differentiate the following compounds below? CH2OH

A B C D

3

OH

Bromine water Carbon dioxide Ethanoyl chloride Diluted hydrochloric acid

Which reaction shows the propagation step during the reaction between methane and chlorine in the presence of light? A B C D

H• + Cl2 CH4 + Cl+ CH4 + Cl+ CH4 + Cl•

HCl + Cl• CH3Cl + H+ CH3+ + HCl •CH3• + HCl

3 4

Which carbon atom can most easily be attacked by an electrophile? A CH2Br H3C D B

5

COCH3 C

Which one of the followings will be produced through the reaction between phenol and chlorine solution?

A

B

CH3

OCl

C OH

Cl D Cl

OH Cl

Cl

4 6

| Which compound can change the C = O group in propanone to | A B C D

7

Chlorine gas Phosphorous (V) chloride Sodium chloride Dilute hydrochloric acid

One component of beeswax, which is used as a car polish, has the formula CH3(CH2)24COO(CH2)29CH3. What are the products of the acidic hydrolysis of this component? A B C D

8

| C — Cl ? |

CH3(CH2)23COOH and CH3(CH2)29COOH CH3(CH2)24COOH and CH3(CH2)28COOH CH3(CH2)24COOH and CH3(CH2)29OH CH3(CH2)24OH, CH3(CH2)OH and CO2

When bromine water is added to phenylamine, the bromine water is decolourised. Which statement explains the observation above? A B C D

Phenylamine oxidises Br2 into Br -. The NH2 group in phenylamine is substituted with Br2. The NH2 group phenylamine reacts with Br2. Bromine substitutes hydrogen in the benzene ring.

5 9

Aspartame is an artificial sweetener which has the structural formula as follows: O O || || H2N — CH — C — NH — CH — C — OCH3 | | CH 2 CH2 | | COOH

Which functional group is not found in the aspartame molecule? A C 10

Ester Carboxyl group

B D

Amino acid Carbonyl group

The repeating unit of a polymer is as follows.

Which of the following can produce the above polymer? A

B

C

6

D

11

12

13

What are the similarities among solid enantiomers (optical isomers)? 1 2 3

Relative molecular mass Melting point Chemical properties

A B C D

1 1,2 2,3 1,2,3

What are the compounds produced when butan-2-ol is refluxed with acidified potassium manganate(VII) solution? 1 2 3

Butanone Butanoic acid Butanol

A B C D

1 1,2 2,3 1,2,3

What is the type of reaction that will occur to the compound below? CH3 CO — CH3

CH = CHCH 3 1 2 3

Electrophilic addition Nucleophilic addition Electrophilic substitution

7 A B C D

14

1 1,2 2,3 1,2,3

A part of a polymer structure is as follows: —NHCO(CH2)4CO2(CH2)2NHCO(CH2)4CO2(CH2)2Which statements are true about this polymer?

15

I 2 3

It can be synthesised from CICO(CH2)4 COC1 and HOCH2CH2NH2. It is a polyamide and also a polyester. It is resistant against alkaline hydrolysis.

A B C D

1 1,2 2,3 1,2,3

There are saturated and unsaturated polymers. Which polymer(s) decolourise(s) an acidified solution of potassium manganate( VII)? 1 2 3

Poly(2-methylbuta-1 ,3-diene) Poly(ethene). Poly(phenylethene)

A B C D

1 1,2 2,3 1,2,3

8 SECTION B [15 marks] Answer all questions in this section. 16

(a) Draw the structure of the major product of each of the following reactions. (i)

-Br +

Ethanol

NH3

(ii) (CH3)2CBr2 + NaOH

(iii)

-CHO

(i) CH3CH2MgBr (ii) H3O+ [3 Marks]

(b) The structural formula of an organic compound is as follows: HO

CH2CHCH3 OH

Draw the structural formula of the organic product(s) formed when the compound reacts with each of the following reagents: (i)

sodium metal

[1 mark]

(ii)

An aqueous solution of sodium hydroxide.

[1 mark]

(iii)

An alkaline iodine solution.

[1 mark]

(iv)

A hot acidic potassium manganate(VII) solution.

[1 mark]

17

(a)

9 Ethene reacts with bromine via electrophile addition mechanism

(i)

What is meant by electrophile? ………………………………………………………………………. ………………………………………………………………………

……………………………………………………………………………… [1 mark] (ii)

Write a balance equation for the reaction the reaction taking place. [2 marks]

(b)

The formulae of polymers X and Y are given below.

(i)

Write the structural formulae of the monomers of polymers X and Y. [3 marks]

(ii)

State the types of polyrnerisation involved in the formation of polymers X and Y.

Polymer X: ………………………………………………………………………… Polymer Y: …………………………………………………………………………

[2 marks]

10 SECTION C [30 marks] Answer any two questions in this section.

18

(a) Identify the type of isomerism shown by 2-butanol and butenedioic acid. Explain why these compounds exhibit isomerism. Draw the pair of isomers for each compound. [6 Marks]

(b) An organic compound P has the molecular formulaC 5H12O ,. P to form Q has a chiral carbon atom and decolourises hot, acidified potassium manganate (VII) solution. Both P and Q forms a yellow precipitate when reacted with an alkaline iodine solution. Q forms a yellow precipitate with 2,4-dinitrophenylhydrazine. Determine the structural formula of P and Q. Explain the above observations and write the appropriate equations for the reactions. [9 Marks ]

19

(a)

(i)

(ii)

(iii)

(b)

Write the mechanism of the reaction when 1-chloropropane is refluxed with aqueous sodium hydroxide. Name the type of reaction involved. [3 marks] State and explain how the rate of this reaction changes when 1-chloropropane is replaced by 1-bromopropane. [3 marks] Write the equations to show how you would change 1-chloropropane to 2-chloropropane. [5 marks]

Catalytic cracking is a process where long chained alkanes are broken into mixture of short chained molecules. (i) (ii)

Explain the importance of the catalytic cracking process in industries. [2 marks] State the conditions required for this process. [2 marks]

11 20 Suggest how each of the following conversions can be carried out. In each case your answer should include successive steps of the conversion and also reagent and condition used in each step. (a)

Ethanol to propanoic acid [4 marks]

(b)

1-propanol to 2-propanol

(c)

2-bromopropane to propanone

(d)

Propane-1-ol to 2-methylpropanoic acid

[3 marks] [3 marks] [5 marks]

END OF QUESTION PAPER

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