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Copper plate / Kepingan kuprum

Zinc sulphate solution

Lautan zink sulfat

Zinc plate / Kepingan zink

Copper(II) sulphate solution Larutan kuprum(II) sulfat

Porous pot / Pasu berliang

3. Diagram 3 shows part of the set up of apparatus of chemical cell.

Rajah3 menunjukkan sebahagian daripada susunan radas bagi sel kimia.

(a) Draw a complete set-up of apparatus for chemical cell on Diagram 3.

Lukiskan susunan radas yang lengkap bagi sel kimia dalam Rajah 3.

[1 mark]

[1 markah]

(b) Label the negative electrode as ( - ) and positive electrode as ( ) on the completed

chemical cell.

Labelkan elektrod negatif sebagai ( - ) dan elektrod positif sebagai ( + ) pada rajah sel

kimia yang telah lengkap.

[1 mark][1 markah]

(c) !tate the flow of electron for the chemical cell in diagram 3.

Nyatakan arah pengaliran elektron bagi sel kimia pada Rajah3.

[1 mark]

[1 markah]

"hat is the function of the porous pot used in the above chemical cell#

Apakah fungsi pasu berliang yang digunakan dalam sel kimia di atas?

[1 mark][1 markah]

"hat can $ou observed at the negative terminal#

Apakah yang boleh anda perhatikan pada terminal negatif?

[1 mark]

[1 markah]

"rite half e%uation for the discharged of ions at positive terminal.

uliskan persamaan setengah bagi ion yang didis!as pada terminal positif.

Diagram 3

Ra ah3

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[1 mark]

[1 markah]

(i) &f the copper plate in the chemical cell above is replaced b$ silver metal' what will

happen to the voltage reading of the cell.

"ika kepingan kuprum di dalam sel kimia di atas digantikan dengan logam argentum#

apakah yang berlaku kepada nilai $oltan yang akan terhasil.

[1 mark]

[1 markah]

(ii) ive the reasons for $our answer.

%erikan sebab bagi ja&apan anda.

[1 mark]

[1 markah]

able 3 shows the voltage of chemical cell using metals *' + and , as the electrode

"adual ' menunjukkan nilai $oltan bagi sel kimia menggunakan logam *' +dan ,

sebagai elektrod.

able 3

"adual '

+ased on the information given' calculate the voltage of a chemical cell using metal * and

+ as the electrodes.

%erdasarkan kepada maklumat yang diberikan# hitungkan nilai $oltan yang akan

dihasilkan oleh sel kimia yang menggunakan logam A dan % sebagai elektrod.

[ marks]

[ markah]

Diagram .1 shows the set up of apparatus for an e/periment to determine the empirical

formula of magnesium o/ide.

Rajah .1 menunjukkan susunan radas bagi suatu eksperimen untuk menentukan formula

empirik magnesium oksida.

0airs of metal

asangan logam

oltage ()

Nilai $oltan ()

positive terminal

terminal positif

+ 2 , .1 ,

* 2 , .4 ,

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Diagram .1

Rajah .1

(a) "hat is the meaning of empirical formula#

Apakah maksud formula empirik#

[1 mark]

[1 markah]

(b) Diagram . shows the results of the e/periment.

Rajah . menunjukkan keputusan e*periment itu.

5ass of crucible lid 6 .44 g

"isim mangkuk pijar penutup

5ass of crucible lid magnesium ribbon 6 7.1 g

"isim mangkuk pijar penutup pita magnesium

5ass of crucible lid magnesium o/ide 6 7.4 g

"isim mangkuk pijar penutup magnesium o8sida

Diagram .

Rajah.

+ased on Diagram .' complete able and determine the empirical formula ofmagnesium o/ide.

%erdasarkan Rajah.' lengkapkan "adual dan seterusnyatentukan formula

empirik bagi magnesium oksida9

[:elative atomic mass9 ; 6 1

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>umber of moles

%ilangan mol

!implest ratio of moles

Nisbah ringkas bilangan mol

=mpirical formula

,ormula empiri!

able

"adual

[< marks]

[< markah]

"rite the chemical e%uation for the reaction in the e/periment.

uliskan persamaan kimia bagi tindak balas dalam eksperimen itu.

[1 mark]

[1 markah]

"h$ the process of heating' cooling and weighing are repeated until a constant mass is

obtained#

engapakah proses pemanasan# penyejukan dan penimbangan diulang sehingga jisim

yang tetap diperolehi#

[1 mark]

[1 markah]

"h$ this e/periment is not suitable to be used to determine the empirical formula of

copper(&&) o/ide#

engapakah eksperimen ini tidak sesuai digunakan untuk menentukan formula empirik

kuprum(&&) oksida#

[1 marks]

[1markah]

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3 (a) 1

(b) Labeling ?inc plate ( - ) and copper plate ( ) 1

(c) @rom ?inc plate to copper plate through the e/ternal circuit 1

(d) o allow the flow of ion from both electrol$te through it to complete

the circuit

1

(e) he ?inc plate becomes thinner 1

(f) ,u

e

,u 1(g) (i) he voltage will be higher 1

(ii) he silver metal is under the copper metal in the electrochemical

series.

1

(h)

* + ,

1

1

(a) (i) he chemical formula that shows the simplest ratio of atoms of the elementspresent in a compound.

1

(b) (i) =lement

nsur5g ;

5ass (g) 7.1 A

.44 22.

7.4 A

7.1 22.1

>umber of

moles

.2 22 .1 .1

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Section B[20 marks]

Answer any onequestion.[Jawab mana-mana satusoalan]

7 Diagram 7 shows the flow chart for the industrial manufacture of sulphuric acid and theproduction of three types of fertilizer.Rajah 7menunjukkan carta alir bagi pembuatan asid sulfurik secara industri dan penghasilantiga jenis baja baja Y ammonium nitrat dan urea.

Diagram 7Rajah 7

(a) (i) ased on step ! to step !" # descri$e $riefly the industrial production ofsulphuric acid.!erdasarkan langkah "hingga langkah!" huraikan secara ringkaspenghasilan asid sulfurik secara industri.

[ % marks]

(ii) &he con'ersion of sulphur dioide to su$stance is 'ery slow and the percentage ofcon'ersion is also 'ery low. *tate three ways to o'ercome this pro$lem.#enukaran sulfur dioksida kepada bahan sangat perlahan dan peratus penukaranjuga sangat rendah.$yatakan tiga cara untuk mengatasi masalah ini.

[ + marks]

(iii) ,rite a chemical e-uation for the reaction $etween sulphuric acid and ammonia toproduce fertilizer Y.%uliskan persamaan kimia bagi tindak balas antara asid sulfurik dan ammonia untukmenghasilkan baja Y.

[ 2 marks]

!ubstance

%ahan !ulphur dio/ide

ulfur dioksida

!ulphur

ulfur

!tep &&

langkah //

!tep 1

Langkah 0 !tep &&&

Langkah ///

!ulphuric acid

Asid sulfurik

;leum

oleum!tep &

Langkah /

*mmonia

Ammonia

@ertiliser E

%aja E

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($) (i) plain why pure copper is softer than its alloy.%erangkan mengapa kuprum tulen lebih lembut daripada aloinya.

[ + mar/s]

(ii) Draw the arrangement of atoms in pure copper and its alloy.&ukis susunan atom dalam kuprum tulen dan aloinya.

[ 2 mar/s]

(iii) *tate the aim of alloying.$yatakan tujuan pengaloian [+ mar/s]

(i') *tate the alloy suita$le for $uilding $odies of planes and gi'e reasons for your answer.$yatakan aloi yang sesuai untuk membina badan pesawat terbang dan berikan sebabbagi jawapan anda.

[+ mar/s]

Questions Marking criteria Marks

7 (a) (i) *ulphur is $urnt in air to produce sulphur dioide urning of metal sulphideszinc sulphide lead sulphideproduce sulphur dioide

*ulphur dioide is oidised to sulphur trioide in ecess oygen

*ulphur trioide is dissol'ed in concentrated sulphuric acidto form oleum.

&he oleum is diluted with water to produce concentratedsulphuric acid

1

1

1

1 %

(ii) &emperature %30 045ressure 1 atmosphere4atalyst "anadium(") oide

111 +

(iii) 62*%8 296+: (96%)2*%;ormula for reactants and product correctalanced

11 +

($)(i) 1. pure metal atoms ha'e similar size and shape.

2.asily to slides

1

12

($)(ii) 1. Draw for pure copper2.Draw for its alloy and la$els for copper and zinc

11

2

($)(iii) 1. increase the strength and hardness of metal2.5re'ent the corrosion of metal+.!mpro'e the appearance

111

2

($)(i') 1.Duralamin2.its strongerharder

+.4an withstand compression

11

1

2

TOTAL 20

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2 able shows the number of subatomic particles of atoms and 1. +oth and 1areisotopes of the same element.

"adual 2 menunjukkan bilangan 3arah sub atom bagi atom dan 1. 4edua-dua dan 1

adalah isotop bagi unsur yang sama.

Atom Number of Protons

Bilangan proton

Number of Neutrons

Bilangan neutron

Number of Electrons

Bilangan elektron

0 < 4 umber of electron each shell correct

%ilangan elektron setiap petala betul] 1

[correct charge and nucleus are shown S s$mbol of element2dotT

!as betul dan pusat ditunjukkanSsimbol unsur 2 titikT ] 1

(iii) 0 F 0F

[ formula of reactant and product correct

,ormula bahan dan hasil tindak balas betul ] 1

[ +alance

eimbang] 1

(d) (i) F: 1

(ii) Low melting point2boiling point 22 insoluble in water2soluble in organic solvent22 cannot

conduct electricit$ in an$ state

[ *n$ two]takat leburCtakat didih rendah CC tidak larut dalam airC larut dalam pelarut

organik CC tidak mengkonduksikan elektrik dalam semua keadaan

[ mana-mana dua] 1 1...10

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