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1 The equation below shows a reaction to produce hydrogen gas.

Persamaan di bawah menunjukkan tindak balas bagi menghasilkan gas hydrogen.

2HCl + ZnZnCl2+ H2

Which of the following would increase the rate of production of hydrogen gas?

Manakah antara pernyataan berikut meningkatkan kadar penghasilan hydrogen gas.

A Increase the time of the reaction

Meningkatkan masa tindak balas

B Increase the volume of acid

Meningkatkan isipadu asid

C Increase the size of granulated zinc

Meningkatkan saiz ketulan zink

D Increase the temperature of the mixture

Meningkatkan suhu campuran

(27/2003)

2 Which of the following can be used to determine the rate of the reaction?

Manakah antara pernyataan berikut dapat digunakan untuk menentukan kadar tindak

balas?

I Release of gas per unit time

Menghasilkan gas per unit masa

II Change of the colour intensity per unit time

Perubahan keamatan warna per unit masa

III Formation of precipitate per unit time

Penghasilan mendakan per unit masa

IV Increase in the mass of reactant per unit time

Meningkatkan jisim bahan tindak balas per unit masa

A I and II only

I dan II sahaja

B III and IV only

III dan IV sahaja

C I, II and III only

I,II dan III sahaja

D II,III and IV onlyII,III dan IV sahaja

(18/2003)

1 |P a g e @ R A T E O F R E A C T I O N S M O D U L E J U J

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3 Table 4 shows the total volume of gas collected at regular intervals in a reaction.

Jadual 4 menunjukkan jumlah isipadu gas yang dikumpul pada sela masa dalam suatu

tindak balas.

Time/s

Masa/s

0 30 60 90 120 150 180 210

Volume of the gas/cm3

isipadu gas/ cm30.0 2.0 3.7 5.2 6.4 7.3 8.6 8.6

What is the average rate of the reaction in the second minute?

Apakah kadar tindak balas purata pada minit kedua?

A 0.040 cm3s-1

B 0.045 cm3s-1

C 0.053 cm3s-1

D 0.062 cm3s-1

(44/2003)

4 The equation below represents the decomposition of hydrogen peroxide solution.

Persamaan berikut mewakili penguraian larutan hidrogen peroksida

2H2O2(aq)2H2O(l) + O2(g)

Which of the following are produced when 1 mole of hydrogen peroxide is decomposed

completely?

Manakah antara berikut yang akan terhasil apabila 1 mol hydrogen peroksida diuraikan

dengan lengkap?

(1 mole of gas occupies 24 dm3at room condition; Avogadros Constant: 6.0 x 1023mol-1

1 mol gas memenuhi 24 dm3pada suhu bilik: Avogadros constant: 6.0 x 1023mol-1)

I 2 mole of water

2 mol air

II 12 dm3 of oxygen gas

12 dm3 oksigen gas

III 3 x 1023of water molecules

3 x 1023molekul air

IV 1.2 x 1024

of water molecules1.2 x 1024molekul air


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A I and III only

I dan III sahaja

B I and IV only

I dan IV sahaja

C II and III only

II dan III sahajaD II and IV only

II dab IV sahaja

(48/2003)

5 The rate of reaction for the decomposition of hydrogen peroxide decreases with the time

because

Kadar tindak balas untuk penguraian hydrogen peroksida berkurangan dengan masa

kerana

A Product of the reaction decreases

Hasil tindak balas berkurangan

B Temperature of hydrogen peroxide decreases

Duhu hydrogen peroksida berkurangan

C Volume of the hydrogen peroxide decreases

Isipadu hydrogen peroksida berkurangan

D Concentration of hydrogen peroxide decreases

Kepekatan hydrogen peroksida berkurangan

(14/2004)


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6 An experiment is carried out to study the rate of reaction between marble and

hydrochloric acid to produce carbon dioxide gas.

Satu eksperimen dijalankan untuk mengkaji tentang kadar tindak balas antara marmar

dengan asid hidroklorik bagi menghasilkan gas karbon dioksida

ExperimentEkperimen

SubstancesBahan

IExcess marble and 50.00 cm3of 2 mol dm-3hydrochloric acid

Marmar berlebihan dan 50.00 cm3asid hidroklorik 2 mol dm-3

IIExcess marble and 100.00 cm3of 1 mol dm-3hydrochloric acid

Marmar berlebihan dan 100.00 cm3asid hidroklorik 1 mol dm-3

Which of the following graphs represents the two experiments?

Manakah antara graf berikut yang mewakili dua eksperimen ini?

A

B

C

D


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7 The reaction between hydrochloric acid and zinc produces hydrogen gas. The reaction is

complete in 50 seconds and the maximum volume of gas produced is 25 cm3. What is the

average rate of the reaction?

Tindak balas antara asid hidroklorik dan zink menghasilkan hydrogen gas. Tindak balas

ini lengkap dalam masa 50 saat dan isipadu gas yang terhasil ialah sebanyak 25 cm 3.

Apakah kadar tindak balas purata dalam tindak balas ini?

A 0.5 cm3s-1

B 1.0 cm3s-1

C 2.0 cm3s-1

D 4.0 cm3s-1

(45/2004)

8 The table shows the mass of sulphur trioxide formed at different temperatures during the

Contact process.

Jadual menunjukkan jisim sulfur trioksida yang terhasil semasa proses Sentuh pada suhu

yang berlainan.

Temperature/oC

Suhu/oC

300 400 500 600

Mass of suphur trioxide/kg

Jisim sulfur trioksida/kg350 200 120 100

Time taken

Masa5 hours 2 hours 6 minutes 9 minutes

At what temperature is the production rate of sulphur trioxide the highest?Pada suhu keberapakah kadar penghasilan tertinggi bagi sulfur trioksida?

A 300 oC

B 400 oC

C 500 oC

D 600 oC

(46/2004)


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9 The diagram shows the energy profile of a reaction. Ea is the activation energy for this

reaction

Gambar rajah menunjukkan profil tenaga bagi suatu tindak balas. Ea adalah tenaga

pengaktifan bagi tindak balas ini.

What will change the activation energy from Ea to Ea?

Apakah yang akan mengubah tenaga pengaktifan daripada Ea ke Ea?

A Temperature

Suhu

B Catalyst

Mangkin

C Concentration

Kepekatan

D Total surface area

Jumlah luas permukaan

(12/2005)

10 Which of the following explains the meaning of effective collision?Antara pernyataan berikut yang manakah menjelaskan maksud perlanggaran yang

berkesan?

A The collision where its energy is less than the activation energy

Perlanggaran yang tenaganya kurang dari tenaga pengaktifan

B The collision that has a low energy

Perlanggaran yang berlaku mempunyai tenaga yang rendah

C The collision which takes place before a reaction

Perlanggran yang berlaku sebelum sesuatu tindak balas

D The collision that causes a reaction

Perlanggran yang menghasilkan tindak balas.

(13/2005)


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11. The diagram shows the set up of the apparatus for an experiment to determine the rate of

the reaction between thiosulphate and sulphuric acid.

Gambar rajah menunjukkan susunan radas bagi eksperimen untuk menentukan kadar

tindak balas antara natrium tiosulfat dengan asid sulfuric.

Which of the following combination of conditions take a shortest time for the mark X to

disappear from sight?

Antara kombinasi keadaan berikut yang manakah mengambil masa paling singkat untuk

tanda X hilang daripada penglihatan?

A

B

C

D

(45/2005)

Sulphuricacid

Sodiumthiosulphate solution

Temperature/oCVolume/cm3

Concentration/mol dm-3

Volume/cm3

Concentration/mol dm-3

10101020

1.01.00.50.5

50505040

0.50.50.50.5

30403040

12. Which of the following isnota characteristic of a catalyst?

Antara yang berikut, yang manakah bukan ciri-ciri mangkin?

A A catalyst is specific in its reaction

Mangkin adalah kursus dalam tindak balasnya.

B A catalyst influences the quality of product reaction

Mangkin mempengaruhi kuantiti hasil tindak balas.

C The chemical property of a catalyst remains unchanged at the end of the reaction

Sifat kimia mangkin tetap tidak berubah di akhir tindak balas.

D Only a little amount of a catalyst is needed to influence of the rate of the reaction

Hanya sedikit mangkin diperluaskan untuk mempengaruhi kadar tindak balas.

(13/2006)


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13. In an experiment, the decomposition of 25 cm3 of 0.1 mol dm-3 hydrogen peroxide

solution produces oxygen gas.

Dalam satu eksperimen, penguraian 25 cm3 larutan hydrogen peroksida 0.1 mol dm-3

menghasilkan gas oksigen. Graf isipadu gas osigen melawan masa dilukis dan lengkung

P diperoleh.

If experiment is repeated using another solution, which solution will produce curve Q?

Sekiranya eksperimen diulang dengan menggunakan larutan lain, larutan manakah yang

akan menghasilkan lengkung Q?

A 25 cm3 of 0.15 mol dm-3hydrogen peroxide

25 cm3 hidrogen peroksida 0.15 mol dm-3

B 20 cm3 of 0.15 mol dm-3hydrogen peroxide


C 15 cm3 of 0.15 mol dm-3hydrogen peroxide


D 10 cm3 of 0.25 mol dm-3hydrogen peroxide


(46/2005)

14. The following statements are related to the collision theory of a reaction.

Antara pernyataan berikut adalah berkaitan dengan teori perlanggaran tindak balas.

I. The total surface area of the reactant particles increases

Jumlah luas permukaan zarah tindak balas meningkat

II. The kinetic energy of the reactant particles increases

Tenaga kinetik zarah bahan tindak balas meningkat

III. The frequency of the collision between the reactant particles increase

Fekuensi perlanggaran antara zarah bahan tindak balas meningkat

IV. The number reactant of particles per one unit of volume increases

Jumlah zarah bahan tindak balas per unit isipadu meningkat


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15. Which of the following combinations is true about the effect of the rise in temperature on

the reactant particles?

Antara kombinasi berikut, yang manakah benar tentang kesan peningkatan suhu ke atas

zarah bahan tindak balas?

A I and II onlyI dan II sahaja

B II and III only

II dan III sahaja

C III and IV only

III dan IV sahaja

D I and IV only

I dan IV sahaja

(30/2006)

16. If you want to cook 100 potatoes within a short time, which is the most suitable method?

Jika anda ingin memasak 100 biji tomato dengan masa yang singkat, manakah kaedah

yang paling sesuai digunakan?

A Boil the potatoes in a pan

Merebus kentang di dalam kuali

B Boil the potatoes in a pressure cooker

Merebus kentang di dalam periuk tekanan

C Steam the potatoes in a steamer

Mengukus kentang di dalam pengukus

D Fry the potatoes in a wok

Menggoreng kentang dalam kuali(43/2006)

17. Which of the following reactants produces the highest rate of the reaction with zinc

powder?

Manakah antara bahan tindak balas berikut yang menghasilkan kadar tindak balas

tertinggi apabila bertindak balas dengan serbuk zink?

A 25 cm3 of sulphuric acid 0.1 mol dm-3

25 cm3 asid sulfurik 0.1 mol dm-3

B 25 cm3 of ethanoic acid 0.1 mol dm-3

25 cm3 asid ethanoik 0.1 mol dm-3

C 25 cm3 of nitric acid 0.1 mol dm-3

25 cm3 asid nitrik 0.1 mol dm-3

D 25 cm3 of hydrochloric acid 0.1 mol dm-3

25 cm3 asid hidroklorik 0.1 mol dm-3

(44/2006)


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18. The reaction between zinc, Zn and hydrochloric acid, HCl is represented by the following

equation.

Zn(s) + HCl(aq)ZnCl2(aq) + H2O(g)

A student wants to determine the rate of the reaction in a school laboratory. Which of the

following methods is the most suitable?

Tindak balas antara zink, Zn dengan acid hydroklorik, HCl diwakili oleh persamaan

berikut.

Zn(s) + HCl(aq) ZnCl2(aq) + H2O(g)

Seorang murid ingin menentukan kadar tindak balas itu di makmal sekolah. Antara

kaedah berikut yang manakah sesuai?

A. Determine the change in temperature of the solution with time

Menentukan perubahan suhu larutan dengan masa

B. Determine the change of the concentration of zinc chloride with time

Menentukan kepekatan zink klorida dengan masa

C. Determine the volume of hydrogen gas given off with time

Menentukan isipadu gas hydrogen yang terbebas dengan masa

D. Determine the change of concentration hydrochloric acid with time

Menentukan perubahan kepekatan acid hidroklorik dengan masa

(12/2007)

19. Diagram 11 shows the apparatus set-up for an experiment to determine the rate of

reaction.

Rajah 11 menunjukan susunan radas bagi ekperimen bagi menentukan kadar tindak

balas.


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20. Which of the following techniques is the most suitable to determine the rate of reaction?

Antara teknik berikut, yang manakah paling sesuai untuk menentukan kadar tindak

balas?

A. Record the time as soon as precipitate is formed.

Mencatat masa apabila mendakan mula terbentuk.B. Record the time to obtain the maximum temperature

Mencatat masa untuk mendapatkan suhu maksimum

C. Record the time as soon as cross mark cannot be seen

Mencatat masa sebaik sahaja tanda pangkah tidak kelihatan.

D. Record the time for the change pH value until the fixed pH value is obtained

Mencatat masa bagi perubahan nilai pH sehingga nilai pH yang tetap diperolehi.

(33/2007)

21. Which is the following is the correct match of a low rate of reaction and a high of

reaction?

Antara padanan berikut, yang manakah betul tentang tindak balas yang mempunyai

kadar tindak balas rendah dan kadar tindak balas tinggi?

Low rate of reaction

Kadar tindak balas rendah

High rate of reaction

Kadar tindak balas tinggi

A Neutralisation between hydrochloric acid

and sodium hydroxide solution

Peneutralan antara acid hidroklorik dan

larutan natrium hidroksida

Iron rusting

Pengaratan besi

B Double decomposition between lead(II)nitrate solution and potassium iodide

solution

Penguraian ganda dua antara larutan

plumbum(II) nitrat dan larutan kalium

iodide

Neutralisation between hydrochloricacid and sodium hydroxide solution

Peneutralan antara acid hidroklorik

dan larutan natrium hidroksida

C Iron rusting

Pengaratan besi

Formation of glucose solution

Penapaian larutan glukosa

D Formation of glucose solution

Penapaian larutan glukosa

Double decomposition between lead(II)

nitrate solution and potassium iodide

solution

Penguraian ganda dua antara larutan

plumbum(II) nitrat dan larutan kalium

iodide

(42/2007)


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22. Table 2 shows the volume of carbon dioxide gas, CO2, collectrd in the reaction between

limestone powder and dilute hydrochloric acid.

Jadual 2 menunjukan isipadu gas carbon dioxide, CO2 yang dikumpul dalam tindak

balas antara serbuk batu kapur dan acid hidroklorik cair.

Time/minuteMasa/minit

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Volumeof CO2/cm3

Isipadu CO2/cm3

0.0 4.5 7.5 10.0 12.5 14.5 16.0 17.0

Table 2

Jadual 2

What is the average rate of reaction during the second minute?

Berapakah kadar tindak balas purata dalam minut kedua?

A. 1.25 cm3minute-1

1.25 cm3minit-1

B. 2.50 cm3minute-1

2.50 cm3minit-1

C. 5.00 cm3minute-1

5.00 cm3minit-1

D. 12.50 cm3minute-1

12.50 cm3minit-1

(43/2007)

23. Which factors does not affect the rate of reaction?

Factor manakah tidak mempengaruhi kadar tindak balas?

A. Size of the solid reactant.

Saiz bahan tidak balas yang berkeadaan pepejal

B. Volume of the reactant.

Isipadu bahan tindak balas

C. Concentration of the reactant

Kepekatan bahan tindak balas

D. Temperature of the reactant

Suhu bahan tindak balas

(8/2008)


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24. Which of the following is a characteristic of a catalyst?

Antara yang berikut adalah ciri suatu catalyst?

A. It changes the amount of product in the reaction

Mengubah kuantiti hasil tindak balas dalam tindak balas

B. Chemically unchanged at the end of the reactionTidak berubah secara kimia pada akhir tindak balas

C. Equal amount of catalyst and reactant are needed for the reaction

Kuantiti yang sama bagi mangkin dan bahan tindak balas diperlukan untuk tindak

balas.

D. The amount of the catalyst decreases at the end of the reactant

Kuantiti mangkin berkurangan pada akhir tindak balas.

(48/2008)

25. Which process have the highest rate of reaction?

Proces yang manakah mempunyai kadar tindak balas yang paling tinggi?

A. Rusting

Pengaratan

B. Respiration

Respirasi

C. Combustion

Pembakaran

D. Photosynthesis

Fotosintesis

(1/2009)

26. In which in the chemical reaction can the rate be determined by measuring the changes in

the gas volume?

Antara tindak balas kimia berikut,yang manakah mempunyai kadar tindak balas yang

boleh ditentukan dengan mengukur perubahan isipadu gas?

A. Acidified potassium manganate(VII) solution with iron(II) sulphate solution

Larutan kalium manganat(VII) berasid dengan larutan ferum(II) sulfat

B. Sodium hydroxide solution with dilute hydrochloric acid

Larutan natrium hidroksida dengan asid hidroklorik cair

C. Silver nitrate solution with sodium chloride solution

Larutan argentum nitrat dengan larutan natrium klorida

D. Calcium carbonate with dilute hydrochloric acid

Kalsium karbonat dengan asid hidroklorik cair

(24/2009)


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27. When the temperature of a reacting mixture increases, the rate of reaction increases.

Which statement explains why the rate of reaction increases?

Apabila suhu campuran bahan tindak balas meningkat, kadar tindak balas meningkat.

Penyataan manakah yang menerangkan mengapa kadar tindak balas meningkat?

A. The total surface area of the reactant particles increasesJumlah luas permukaan zarah-zarah bahan tindak balas bertambah.

B. The total number of the reactant particles per unit volume increases.

Jumlah bilangan zarah-zarah bahan tindak balas per unit isi padu bertambah.

C. The reactant particles move faster and collide more often with one another.

Zarah-zarah bahan tindak balas bergerak lebih cepat dan berlanggar lebih kerap

antara satu sama lain.

D. The reactant particles which collide more often are able to overcome the lower

activation energy.

Zarah-zarah bahan tindak balas yang berlanggar lebih kerap boleh mengatasi

tenaga pengaktifan yang lebih rendah.

(30/2010)

28. Table 6 shows the total volume of hydrogen gas, collected at regular intervals for the

reaction between zinc and hydrochloric acid.

Jadual 6 menunjukkan jumlah isi padu gas hydrogen, yang dikumpul pada sela masa yang

sekata bagi tindak balas antara zink dan asid hidroklorik.

Time (min)

Masa (min)

Total volume of hydrogen gas (cm3)

Jumalah isi padu gas hydrogen (cm3)

0.0 0.00

0.5 8.001.0 14.50

1.5 20.50

2.0 24.00

2.5 26.50

3.0 26.50

3.5 26.50

What is the average rate of reaction?

Berapakah kadar tindak balas purata?

A. 0.10 cm3min-1

B. 7.60 cm3min-1

C. 10.60 cm3min-1

D. 37.40 cm3min-1

(31/2010)


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29. The following equation shows the reaction between zinc powder and hydrochloric acid.

Persamaan berikut menunjukkan tindak balas antara serbuk zinc dengan asid

hidroklorik.

Zn + 2HCl ZnCl2+ H2

How can the rate of production of hydrogen can be increased?

Bagaimanakah kadar penghasilan hydrogen boleh ditingkatkan?

A. Increase the size of zinc

Meningkatkan saiz zink

B. Increase the volume of water in the acid

Meningkatkan isipadu air dalam asid

C. Increase the volume of hydrochloric acid

Meningkatkan isipadu asid hidroklorik

D. Increase the temperature of the hydrochloric acid

Meningkatkan susu acid hidroklorik

(32/2010)

30. The following chemical equation represents the reaction between calcium carbonate,

CaCO3and hydrochloric acid, HCl.

CaCO3(s) + 2HCl(aq)CaCl2(aq) + CO2(g) + H2O(l)

Which changes can be used to determine the rate of reaction?

Persamaan kimia berikut mewakili tindak balas antara kalsium karbonat, CaCO3 dan

asid hidroklorik, HCl.


Perubahan manakah boleh digunakan untuk menentukan kadar tindak balas?

I Mass of calcium carbonate per unit time

Jisim kalsium karbonat per unit masa

II Volume of carbon dioxide released per unit time

Isi padu karbon dioksida dibebaskan per unit masa

III Colour of solution per unit time

Warna larutan per unit masa

IV Mass of precipitate produced per unit time

Jisim mendakan terhasil per unit masa

A. I and II

B. I and III

C. II and IV

D. III and IV

(24/2011)


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31. When a few drops of copper(II) sulphate solution is added to a mixture of zinc powder

and dilute sulphuric acid, the rate of reaction increases. Which statement best explains

why the rate of reaction increases?

Apabila beberapa titik larutan kuprum(II) sulfat ditambah kepada campuran serbuk zink

dan asid cair, kadar tindak balas meningkat. Pernyataan manakah yang terbaik

menjelaskan mengapa kadar tindak balas meningkat?

A. Lowers the activation energy

Merendahkan tenaga pengaktifan

B. Increases the collision frequency

Meningkatkan frekuensi perlanggaran

C. Increases the concentration of sulphate ion in the mixture

Meningkatkan kepekatan ion sulfat dalam campuran

D. Makes the orientation of collision between reacting particles is favourable

Menjadikan orientasi perlanggaran antara zarah bahan tindak balas lebih sesuai.

(29/2011)

32. Table 4 shows the total volume of oxygen gas, O2, collected in the decomposition

reaction of hydrogen peroxide, H2O2.

Jadual 4 menunjukkan jumlah isipadu gas oksigen, O2, yang dikumpul dalam tindak

balas penguraian hydrogen peroksida, H2O2.

Time(s)

Masa(s)0 30 60 90 120 150 180 210 240

Volume of O2(cm3)

Isipadu O2 (cm3)

0.00 18.00 27.50 35.00 41.50 46.50 50.00 50.00 50.00

Table 4Jadual 4

What is the overall average rate of reaction?

Berapakah kadar tindak balas purata keseluruhan?

A. 0.152 cm3s-1

B. 0.208 cm3s-1

C. 0.278 cm3s-1

D. 0.310 cm3s-1

(39/2011)


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Section A

Bahagian A

1 Diagram 6 shows two experiments to investigate one factors that influences the rate of a

reaction.

Rajah 6 menunjukkan dua eksperimen untuk mengkaji satu faktor yang mempengaruhi

kadar satu tindak balas.

(a) What is the factor that influences the rate of reaction in both experiments?

Apakah faktor yang mempengaruhi kadar tindak balas dalam kedua-dua

eksperimen itu?

[1 mark]


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(b) The reaction in the experiment is represented by the following equation:


Tindak balas dalam eksperimen itu diwakili oleh persamaan berikut:

CaCO3(p) + 2HCl(ak) CaCl2(ak) + CO2(g) + H2O(ce)

(i) Among the products stated in the equation, which is the most suitable to

be chosen to determine the rate of reaction?

Antara hasil tindak balas yang dinyatakan dalam persamaan ini, yang

manakah paling sesuai untuk menentukan kadar tindak balas?

[1 mark]

(ii) State one reason for choosing the product in 1(b)(i).

Nyatakan satu sebab untuk memilih hasil tindak balas di 6(b)(i).

[1 mark]

(c) State two controlled variable in both experiment.

Nyatakan dua pembolehubah yang dimalarkan dalam kedua-dua eksperimen ini.

[2 marks]


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(d) The results for both experiments are represented by Graph 6.

Keputusan kedua-dua eksperimen itu diwakili oleh graf 6

Based on Graph 6:

Berdasarkan Graf 6:

(i) Experiment II has a higher rate of reaction. How does the graph show

this?

Eksperimen II menunjukkan kadar tindak balas yang lebih tinggi.

Bagaimanakah graf itu menunjukkan keadaan ini?

[1 mark]

(ii) What is happen to the reactant at timex?

Apakah yang telah berlaku pada bahan tindak balas pada masa x?

[1 mark]

(iii) Why are both curves at the same level after timex?

Mengapakah kedua-dua lengkung berada pada aras yang sama selepas

masa x?

[1 mark]


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(e) What is the conclusion for both experiments?

Apakah kesimpulan bagi kedua-dua eksperimen itu?

[1 mark]

(f) Another experiment is carried out using excess calcium carbonate powder and

dilute hydrochloric acid with different concentrations.

Satu eksperimen lain dijalankan menggunakan serbuk kalsium karbonat

berlebihan dengan asid hydroklorik cair yang berlainan kepekatan.

Sketch the curve of concentration of dilute hydrochloric asid against the time

taken to collect a fixed quantity of the product.

Lakar lengkung graf kepekatan asid hidroklorik cair melawan masa untuk

mengumpul kuantiti hasil ditetapkan.

[2 marks]


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2 An experiment is carried out to investigate the rate of reaction of zinc with hydrochloric

acid. Excess zinc powder is added to 20 cm3 of 0.2 mol dm-3 hydrochloric acid. The

volume of gas collected at regular intervals is shown in Diagram 5.1

Satu eksperimen dijalankan untuk mengkaji kadar tindak balas antara zink dengan asid

hidroklorik. Serbuk zink berlebihan ditambah kepada 20 cm3asid hidroklorik 0.2 mol dm-

3

. Isi padu gas yang terkumpul pada sela masa yang sama ditunjukkan dalam Rajah 5.1.

(a) State the meaning of the rate of reaction.

Nyatakan maksud kadar tindak balas.

[1 mark]

(b) From the graph in Diagram 5.1, determine:

Daripada graf dalam Rajah 5.1, tentukan:

(i) The rate of reaction at 120 s.

Kadar tindak balas pada 120 s

[1 mark]

(ii) The average rate of reaction between 60 s and 120 s.

Kadar tindak balas purata antara 60 s dan 120 s.

[1 mark]


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(c) Explain why the rate of reaction decreases with time.

Terangkan mengapa kadar tindak balas berkurangan dengan masa.

[1 mark]

(d) Another experiment is carried out to study the factors that affect the rate of this

reaction. The results of this experiment are shown in Diagram 5.2. Curve I

represents the results of this experiment using excess zinc powder and 50 cm3of

1.0 mol dm-3dilute hydrochloric acid.

Satu eksperimen lain dijalankan untuk mengkaji faktor-faktor yang

mempengaruhi kadar tindak balas ini. Keputusan eksperimen ini ditunjukkan

dalam Rajah 5.2. Lengkung I mewakili keputusan eksperimen yang menggunakan

serbuk zink berlebihan dan 50 cm3asid hidroklorik cair 1.0 mol dm-3.

(i) Suggest the factors that influence the rate of reaction to obtain the curveslabelled II and III

Cadangkan faktor yang mempengaruhi kadar tindak balas untuk

mendapatkan lengkung-lengkung berlabel II dan III

Curve II/ lengkung II : .

Curve III/ lengkung III :.

[2 marks]


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(ii) Describe briefly how to carry out the experiment to obtain the curve

labelled III.

Huraikan dengan ringkas bagaimana eksperimen itu dijalankan untuk

mendapatkan lengkung berlabel III.

[3 mark]

(iii) Give one reason why the final volume the gas obtained in curve III is

half the final volume of gas in curve I.

Beri satu sebab mengapa isi padu akhir gas yang terhasil dalam

lengkung III adalah separuh daripada isi padu gas dalam lengkung I.

[1 mark]


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3 Diagram 5 show two set of experiment to study the factor affecting the rate of reaction

between hydrochloric acid, HCl and calcium carbonate, CaCO3

Rajah 5 menunjukkan dua set eksperimen untuk mengkaji faktor yang mempengaruhi

kadar tindak balas antara asid hidroklorik, HCl dan kalsium karbonat,CaCO3.

(a) Write a balanced chemical equation for this reaction in this experiment.

Tulis persamaan kimia seimbang bagi tindak balas dalam eksperimen ini.

[2 marks]

(b) What is the reading needed to recorded in both experiments to determine the rate

of reaction in 3 minutes?

Apakah bacaan yang perlu dicatat dalam kedua-dua eksperimen untuk

menentukan kadar tindak balas dalam masa 3 minit?

[1 mark]


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(c) Calculate the average rate of reaction in set I

Hitung kadar tindak balas purata dalam set I

(d) (i) Compare the rate of reaction in set 1 and set 2.

Explain your answer based on the factor affecting the rate of reaction.

Bandingkan kadar tindak balas bagi set 1 dan set 2. Jelaskan jawapan

anda berdasarkan faktor yang mempengaruhi kadar tindak balas.

[2 marks]

(ii) Explain the answer in 5(d)(i) with reference to the collision theory.

Jelaskan jawapan di 5(d)(i) dengan merujuk kepada teori perlanggaran.

[3 marks]


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(e) Sketch the graph of volume of carbon dioxide gas produced against time for both

set of experiment in the first 3 minutes.

Lakarkan graf isi padu gas karbon dioksida yang dihasilkan melawan masa bagi

kedua-dua set eksperimen dalam masa 3 minit yang pertama.

Volume ofcarbon dioxide/

cm3

Isipadu karbon

dioksida / cm3

Time/ min

Masa/min

4 In an experiment to investigate the rate of reaction, 50.0 cm3 of 0.2 mol dm-3 sodium

thiosulphate solution and 5.0 cm3of mol dm-3of sulphuric acid, are used. The sulphur

formed can be measure the rate of reaction.

Dalam satu eksperimen untuk mengkaji kadar tindak balas, 50.0 cm3

larutan tiosulfat 0.2mol dm-3 dan 5.0 cm3 asid sulfurik 1.0 mol dm-3, digunakan. Sulphur yang terbentuk

boleh digunakan untuk mengukur kadar tindak balas itu.

The equation for the reaction is given below.

Persamaan tindak balas itu diberi di bawah.

Na2S2O3+ H2SO4Na2SO4+ SO2+ S + H2O

(a) What is the colour of sulphur?

Apakah warna sulphur?

[1 mark]


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(b) The number of moles of a solute can be calculated using the formula, n=MV

[ n = Number of moles of solute (mol), M = Molarity of a solution(mol dm-3),

V = Volume of solution(dm-3)]

Bilangan mol suatu zat terlarut boleh dihitung menggunakan rumus, n=MV

[ n = Bilangan mol zat terlarut (mol), M = Kemolaran larutan (mol dm-3), V =

Isipadu larutan (dm-3

)]

Calculate,

Hitung,

(i) The number of mole of sodium tiosulphate in the solution.

Bilangan mol bagi natrium tiosulfat dalam larutan itu.

[1 mark]

(ii) The number of mole of sulphuric acid.

Bilangan mol bagi asid sulfurik.

[1 mark]

(c) Based on the answer in 2(b)(i) and 2(b)(ii), name the reactant which determines

the quantity of sulphur formed at the end of the reaction.

Berdasarkan jawapan di 2(b)(i) dan 2(b)(ii), namakan bahan tindak yang

menentukan kuantiti sulphur yang terbentuk pada akhir tindak balas itu.

[1 mark]

(d) (i) State three factors that can affect the rate of reaction in this experiment.

Nyatakan tiga faktor yang boleh mempengaruhi kadar tindak balas itu

dalam eksperimen ini.

1. .

2. .

3. .

[3 marks]


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(ii) using the collision theory, explain how any one of the factors in 2(d)(i)

increases the rate of reaction.

Menggunakan teori perlanggaran, terangkan bagaimana mana-mana

satu daripada faktor di 2(d)(i) meningkatkan kadar tindak balas.

[2 marks]


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Section B

Bahagian B

1 (a) Food stored in a refrigerator lasts longer than food stored in a kitchen

cabinet. Explain why.

[4 marks]

Makanan yang disimpan dalam peti sejuk tahan lebih lama daripada makananyang disimpan dalam almari dapur.

Terangkan mengapa.

[4 markah]

(b) A group of pupils carried out three experiments to investigate the factors

affecting the rate of reaction. Table 7 shows information about the reactant and

the temperature used in each experiment.

Sekumpulan murid telah menjalankan tiga eksperimen untuk mengkaji kesan

faktor-faktor yang mempengaruhi kadar tindak balas. Jadual 7 menunjukkan

maklumat tentang bahan tindak balas dan suhu yang digunakan dalam setiap

eksperimen.

Experiment

Eksperimen

Reactants

Bahan tindak balas

Temperature/C

Suhu/C

I

Excess calcium carbonate chips and 30 cm3of 0.5 mol

dm-3hydrochloride acid

Ketulan kalsium karbonat berlebihan dan 30 cm3asid

hidroklorik 0.5 mol dm-3

30

II

Excess calcium carbonate chips and 30 cm3of 0.5 mol

dm-3hydrochloride acid

Ketulan kalsium karbonat berlebihan dan 30 cm3asid

hidroklorik 0.5 mol dm-3

40

III

Excess calcium carbonate powder and 30 cm3of 0.5

mol dm-3hydrochloride acidSerbuk kalsium karbonat berlebihan dan 30 cm3asidhidroklorik 0.5 mol dm-3

40

Table 7

Jadual 7

Graph 7 shows the results of these experiments.

Graf 7 menunjukkan keputusan eksperimen-eksperimen ini.


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(i) Calculate the average rate of reaction for Experiment I.

Hitungkan kadar tindak balas purata bagi eksperimen I.

[2 marks]

(ii) Based on Table 7 and Graph 7, compare the rate of reaction between:

Berdasarkan Jadual 7 dan Graf 7, bandingkan kadar tindak balasantara:

Experiment I and experiment II

Eksperimen I dan eksperimen II

Experiment II and experiment III

Eksperimen II dan eksperimen III

In each case explain the different in rate of reaction with reference to the

collision theory.

Bagi setiap kes terangkan perbezaan dalam kadar tindak dengan

merujuk kepada teory perlanggaran.

[10 marks]


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(iii) The chemical equation below shows the reaction between calcium

carbonate and hydrochloric acid.

Persamaan kimia di bawah menunjukkan tindak balas antara kalsium

carbonate dengan asid hidroklorik.

CaCO3+ 2HClCaCl2+ CO2+ H2O

Given that the relative atomic mass of C=12, O=16, Ca=40 and the molar

volume of any gas is 24 dm3mol -1at room temperature and pressure.

Diberi, jisim atom relatif bagi C=12, O=16, Ca=40 dan isi padu molar

sebarang gas adalah 24 dm3 mol-1 pada suhu dan tekanan bilik.

Calculate the maximum volume of carbon dioxide gas produced in

Experiment II.

Hitungkan isipadu maksimum gas karbon dioksida yang terhasil dalam

eksperimen II.

[4 marks]

2 Three experiments, I, II, and III are carried out to investigate the factors affecting the rate

of reaction. Table shows the reactants and the conditions of reaction involved.

Tiga eksperimen, I, II, dan III dijalankan untuk mengkaji faktor-faktor yang

mempengaruhi kadar tindak balas. Jadual 8 menunjukkan bahan tindak balas dan

keadaan tindak balas yang terlibat.

Experiment

Eksperimen

Reactants

Bahan tindak balas

Condition of reaction

Keadaan tindak balas

I Excess zincZink berlebihan

50 cm3 of 0.5 mol dm-3

hydrochloric acid50 cm3 asid hidroklorik 0.5

mol-3

Room temperature

IIExcess zinc

Zink berlebihan


sulphuric acid

50 cm3asid sulfurik 0.5 mol-3

Room temperature

IIIExcess zinc

Zink berlebihan


sulphuric acid

50 cm3asid sulfurik 0.5 mol-3

60C

(a) (i) Referring to experiment I, II and III, state:

The meaning of rate of reaction Two factors that affect the rate of reaction

Merujuk kepada eksperimen I, II dan III, nyatakan:

Maksud kadar tindak balas,

Dua faktor yang mempengaruhi kadar tindak balas

[3 marks]


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(ii) Write a balanced chemical equation for the reaction in experiment I

Tulis persamaan kimia seimbang bagi tindak balas dalam eksperimen I.

[2 marks]

(b) Calculate the total volume of hydrogen gas released in experiment I.

[Molar gas volume at room conditions is 24 dm3]

Hitungkan jumlah isipadu gas hydrogen yang dibebaskan dalam eksperimen I.

[Isi padu molar gas pada keadaan bilik ialah 24 dm3]

[3 marks]

(c) Diagram 8 shows the results of experiments I, II and III.

Rajah 8 menunjukkan keputusan bagi eksperimen I, II dan III.

Based on the graph,

Berdasarkan graf,

(i) Compare the rate of reaction between experiment I and experiment II.

Explain your answer using the Collision Theory.

Banding kadar tindak balas antara eksperimen I dan eksperimen II.Jelaskan jawapan anda menggunakan Teori Perlanggaran.

[5 marks]


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(ii) Suggest one way to obtain curve III without changing the zinc, acid or

temperature in experiment II. Explain your answer using collision theory.

Cadangkan satu cara untuk memperoleh lengkung tiga tanpa mengubah

zinc, asid, dan suhu dalam eksperimen II. Jelaskan jawapan anda

menggunakan teori Perlanggaran.

[5 marks]

(iii) Explain why the total volume of hydrogen gas released in experiment II

is doubled that of experiment I.

Terangkan mengapa jumlah isi padu gas hydrogen yang dibebaskan

dalam eksperimen II adalah dua kali ganda eksperimen I.

[2 marks]

Section C

Bahagian C

1 Table 10 shows the data from Experiment I and Experiment II that were carried out to

study the rate of reaction of zinc with two acid,Pand Q.

Jadual 10 menunjukkan data daripada Eksperimen I dan Eksperimen II yang dijalankan

untuk mengkaji kadar tindak balas antara dua asid, P dan Q.

Experiment

Eksperimen

Reactants

Bahan tindak balas

Products

Hasil tindak balas

Observation

Pemerhatian

I

2.6 g of zinc and 50 cm3of

acidP2.0 mol dm-3

2.6 g of zink dengan 50

cm3asid P 2.0 mol dm-3

Zinc chloride and

hydrogen gas

Zink klorida dan gas

hidrogen

The temperature of the

mixture inceases

Suhu campuran meningkat

II

2.6 g of zinc and 50 cm3of

acid Q2.0 mol dm-3

2.6 g of zink dengan 50cm3asid Q 2.0 mol dm-3

Zinc sulphate and

hydrogen gas

Zink sulfat dan gas

hidrogen

The temperature of the

mixture inceases

Suhu campuran meningkat


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(a) (i) By choosing either Experiment I or Experiment II, state the name of

the acid used. Write the chemical equation for the reaction of this acid

with zinc.

Dengan memilih Eksperimen I atau Eksperimen II, nyatakan nama asid

yang digunakan . tulis persamaan kimia bagi tindak balas ini dengan

zink.[2 marks]

(ii) Draw an energy profile diagram for the reaction in 10(a)(i). On the

energy profile diagram show the:

Lukis satu gambar rajah profil tenaga untuk tindak balas di 10(a)(i).

Pada gambar rajah profil tenaga itu ditunjukkan:

Heat of reaction, H

Haba tindak balas, H

Activation energy without a catalyst,Ea

Tenaga pengaktifan tanpa mangkin, Ea

Activation energy with a catalyst,Ea

Tenaga pengaktifan dengan mangkin, Ea

Explain the energy profile diagram.

Jelaskan gambar rajah profil tenaga itu.

[10 marks]


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(b) The graph in Diagram 10 shows the results of Experiment I and Experiment II

Graf pada Rajah 10 menunjukkan keputusan bagi Eksperimen I dan Eksperimen

II.

Based on the graph:

Berdasarkan pada graf:

(i) Calculate the average rate of reaction for either Experiment I or

Experiment II.

Hitungkan kadar tindak balas purata bagi Eksperimen I atau

Eksperimen II.

[2 marks]

(ii) Explain the different in the rate of reaction between Experiment I and

Experiment II before 160 s. Use the collision theory in your explanation.

Terangkan perbezaan kadar tindak antara Eksperimen I dan Eksperimen

II sebelum 160 s. Gunakan teori perlanggaran dalam penerangan anda.

[6 marks]


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PAPER 3 : CHAPTER 1 FORM FIVE (Rate of Reaction)

Q1 / P3 / 2003

An experiment was conducted to find out the effects of temperature on the rate of reaction. 50

cm3of sodium thiosuiphate solution 0.05 mol dm-3 at 30C was put into a 250 cm3conical flask.

Then the conical flask was placed on an `X' sign on a piece of white paper.

10 cm3of hydrochloric acid 1.0 mol dm3was added to the sodium thiosuiphate solution andshaken. At the same time, the stop watch was started. The stop watch was stopped as soon as the

`X' sign was no longer visible. The same steps of the experiment were repeated for sodium

thiosuiphate solution which was heated to 35C, 40C and 50C.

Figure 1 shows the readings of the stop watch for each of the reaction at different temperatures.

Diagram 1

(a) Record the time for each reaction in the spaces provided in Diagram 1.


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(b) Construct a table and record temperature, time, andtime

1 for this experiment.

(c) (i) Draw a graph of temperature againsttime

1 on the graph paper.

(ii) Based on the graph in (c)(i), state the relationship between the rate of

reaction and temperature.

(d) Predict the time taken as soon as the sign `X' to be no longer visible if

this experiment is repeated at 55C.

(e) (i) State the variable involved in this experiment.

Manipulated variable

Responding variable

Constant variable


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(ii) State how you would manipulate one variable while keeping the other

variable constant.

(f) State the hypothesis for this experiment.

.

.

(g) From the above experiment, the student found a relationship between

temperature and rate of reaction. The same situation can be applied in our dailylives, for example, keeping food that is easily spoiled in the refrigerator.

Using your knowledge of chemistry, state the relationship between temperature

and the rate at which food turns bad.

..

..

..


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MARK SCHEME

1. D 30. C2. C 31. A3. C 32. C4. C

5. D6. D7. A8. B9. B10. D11. B12. B13. C14. B15. B16. A

17. C18. C19. D20. C21. B22. B23. C24. D25. C26. C27. D28. C

29. D

Section A

1. (a) Total surface area of the calcium carbonate

(b)(i) Carbon dioxide, CO2

(b)(ii) The volume of carbon dioxide released per unit time can be easily measured

(c) 1. The temperature of the reacting mixture

2. The concentration of the hydrochloric acid

(d)(i) The gradient of the graph obtained from Experiment II is much steeper that the

gradient of the graph obtained from experiment I.

(d)(ii) One of the reactant and both of the reactants has completely reacted.(d)(iii) The mass of calcium carbonate or the number of moles of hydrochloric acid used

is the same in both experiments. This resulted in the same volume of carbon

dioxide being released.

(e) The bigger the total surface area is, the higher the rate of reaction will be.


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(f)

2. (a) Rate is a measure of how fast or how slow something is happening.

In chemistry, the rate of reaction is the speed at which reactants are converted

into products through a chemical reaction.

Concentration of dilute

hydrochloric acid

Time taken to collect a

fixed quantity of product

(b)(i) Rate of reaction

=

= 0.142 cm3s-1

(b)(ii)

=

= 0.267 cm3s-1

(c) Because the concentration of the acid and the mass of the zinc decreases with

time

(d)(i) Curve II : The experiment is carried out at a higher temperature or a catalyst is

used.

Curve III : The experiment is carried out with a lower concentration of HCl or

with a smaller mass of zinc.

(d)(ii) The experiment for curve (III) are carried out, using the same apparatus set up

and under the same condition as in experiment (I). However, only the

concentration of HCl is changed from 1.0 mol dm-3 to 0.5 mol dm-3. The

volume of the gas collected at regular interval by using water displacement

method.

(d)(iii) Because the reaction uses the same volume of HCl but with half of its

concentration. Therefore, the number of mole of hydrochloric cid for curve III is

half the number of mole of HCl for curve I.

3. (a) CaCO3+ 2HClCaCl2+ CO2+ H2O

(b) Volume of carbon dioxide released every 30 seconds.

(c) 60 (3 60) = 0.333 cm3s-1

(d)(i) The rate in reaction in set 2 is higher than the rate of reaction in set 1. This is

because the concentration of HCl in reaction in set 2 is higher than that in

reaction in set 1. The higher the concentration, the higher is the reaction will.be.


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(d)(ii) A higher concentration of HCl contains more particles of H+ and Cl- per unit

volume, the higher the effective rate of collision of H+ on CO32- will be. This

increases the rate of formation of CO2.

(e)

Section B.

1. (a) Food stored in a refrigerator lasts longer because of the following reasons :

The temperature in refrigerator is lower

Bacterial activity is lower, less toxin is produced by bacteria

In a kitchen cabinet, the temperature is higher, bacterial activity is higher.

Therefore the rate of food spoilage is faster in a kitchen cabinet than in a

refrigerator.

(b)(i) Volume of gas released = 50 cm3

Time taken = 55 s

Therefore the average rate of reaction

=

= 0.91 cm3s-1

(b)(ii) Experiment I and experiment II

Experiment II has a higher rate of reaction than experiment I.

The temperature for reaction II is higher than experiment I.

Frequency collision between hydrogen ion, H+ and calcium carbonate

increases in experiment II, so

The kinetic energy between reacting particles increases, so

The frequency of effective collision between reactant particles increases.

Experiment II and experiment III

The rate of reaction in experiment III is higher than experiment II

The size of calcium carbonate in experiment III is smaller than experiment II

The smaller the size, will increases the total surface area in experiment III

The frequency of collision between hydrogen ion, H+and calcium carbonate

increases.

The frequency of effective collision between reactant particles increases.


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(b)(iii) Number of mole of hydrochloric acid

= x 30

= 0.015 moles

2 moles of HCl produce 1 mol of carbon dioxide

Therefore 0.015 mole hydrochloric acid produces= x 0.015

= 0.0075 mole

1 mole of CO2 occupies 24 000 cm3

Therefore 0.0075 mole will occupy

= 0.0075 x 24 000 cm3

= 0.18 dm3

2. (a)(i) Meaning

Rate of reaction is the change of volume of hydrogen gas per unit volume

Two factorsTemperature and concentration of hydrogen ion/ hydrochloric

(a)(ii) Zn + 2HClZnCl2+ H2

(b) Number of mole

= = = 0.025

= = 0.0125

Total volume

= 0.0125 X 24 = 0.3 dm3

(c)(i) Experiment I and experiment II

Rate of reaction of experiment II is higher than experiment I

Concentration of hydrogen ions in experiment in experiment II is higher than

experiment I

Thus, the number of hydrogen ion per unit volume in experiment II is higher

than experiment I

Frequency of collision between zinc and hydrogen ion in experiment II is

higher than experiment I

Frequency of effective collisions between particles increases

(c)(ii) Add a catalyst such as copper(II) sulphate

The catalyst lowers the activation energy.

More particles collide with each other to achieve activation energy.

Frequency of collisions between zinc and hydrogen ion increases. Frequency of effective collisions between particles increases

(c)(iii) The acid used in experiment II is diprotic acid whereas in experiment I

is monoprotic.

So, the number of hydrogen ions in experiment II is double.


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Section C.

1. (a)(i) Experiment I : Hydrochloric acid

Zn + 2HCl ZnCl2+ H2

(a)(ii)

Explanation Ea

The reaction is exothermic

The total heat contains of the products is lower than that of the reactant

Therefore heat of given off.

The differences between reactants and products are known as the heat of

reaction.

The energy differences between the maximum energy of the curve and the

energy of the reactant are called activation energy.

This is the energy barrier that must be overcome before the reaction can occur.

Explanation Ea When a catalyst is added, the activation energy is lower.

The reaction goes through an easier path

The rate of reaction increases because more effective collision between the

reactant particles can occur to produce the products faster.

(b)(i) Experiment I

= = 4 cm3s-1

(b)(ii) Experiment I.

The acid used in experiment I is hydrochloric acid. It is a monoprotic acid. The

acidproduces one hydrogen ion per molecule.

Experiment II

The acid used in experiment II is sulphuric acid. It is a diprotic acid. The acid

produces two hydrogen ions per molecule. If the concentration is the same,

diprotic acid will have more hydrogen ions per unit volume than a monoprotic


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acid. The frequency of effective collision between reactant particles is higher.

This will result in a higher rate of reaction for experiment II.

Paper 3 :

1 (a) Time, t155 s at the temperature of 30 C.

Time, t248 a at the temperature of 35 C.

Time,t3 42 a at the temperature of 40 C.

Time. t437 s at the temperature of 45 C.

Time, t5 33 a at the temperature of 50 C.

(b)

(1) Graph of temperature againsttime

1


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(ii) The rate of reaction increases with the increase in temperature.

From the graph, when temperature = 55 C,time

1= 0.033 s-1

Time = 30.3 s

(h) (i) Manipulated variable: Temperature of sodium thiosulphate solution.

Responding variable: Rate of reaction between sodium thiosuiphate

and hydrochloric acid.

Constant variable: Concentration and volume of sodium thiosulphate solution

and hydrochloric acid.

(ii) Temperature is the manipulated variable.

Heating sodium thiosulphate with several different temperatures by remaining the

concentration and volume of sodium thiosulphate solution and hydrochloric acid

constant helps maintain the responding variable.

(i) The higher the temperature, the higher the rate of reaction is.

(g) The lower the temperature, the lower the rate of food turns bad.

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