Bab 6 Elektrokimia Elektrolisis Sebatian Akues.docx

ELEKTROKIMIA [Elektrolisis Sebatian Akues] BAB 6 LATIHAN TAJUK TOPIK 1

: : BAB 6 – ELEKTROKIMIA : ELEKTROLISIS SEBATIAN AKUES (OBJEKTIF)

Diagram 1 shows the set-up of apparatus for the electrolysis of copper(II) nitrate solution? Rajah 1 menunjukkan susunan radas bagi elektrolisis larutan kuprum(II) nitrat?

Diagram 1 Rajah 1 The intensity of the blue colour of copper(II) nitrate is decreasing. Which of the following explains the observations? Keamatan warna biru larutan kuprum(II) nitrat didapati berkurang. Antara berikut, yang manakah menerangkan pemerhatian ini? A OH- ion is discharged at the anode Ion OH- dinyahcas di anod B H+ ion is discharged at the cathode Ion H+dinyahcas di katod C NO3- ion is discharged at the anode Ion NO3- dinyahcas di anod D Cu2+ ion is discharged at the cathode Ion Cu2+ dinyahcas di katod Aras sederhana 2

Which of the following factor does not affect the electrolysis of an aqueous solution? Antara factor berikut, yang manakah tidak mempengaruhi elektrolisis larutan akueus? A Volume of electrolytes used in the electrolysis Isi padu elektrolit yang digunakan dalam elektrolisis B Types of electrodes used in the electrolysis Jenis elektrod yang digunakan dalam elektrolisis C Concentration of ions in the electrolytes Kepekatan ion dalam elektrolit D Position of ions in the electrochemical series Kedudukan ion-ion dalam siri elektrokimia Aras rendah

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What are the ions present in aqueous potassium sulphate? Apakah ion-ion yang hadir dalam larutan kalium sulfat? A K , SO4 C K+, H+, SO42+ 2B K , SO4 D K+, H+, SO42-, OHAras sederhana

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ELEKTROKIMIA [Elektrolisis Sebatian Akues] BAB 6 4

Which of the following electrolyte produces hydrogen gas and oxygen gas during electrolysis using carbon compounds? Antara elektrolit berikut, yang manakah akan menghasilkan gas hidrogen dan gas oksigen semasa elektrolisis menggunakan elektrod karbon? A Sodium chloride solution C Zinc iodide solution Larutan natrium klorida Larutan zink iodida B Copper(II) sulphate solution D Magnesium sulphate solution Larutan kuprum(II) sulfat Larutan magnesium sulfat Aras tinggi

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Which substance conducts electric current in aqueous state? Bahan manakah yang mengkonduksikan elektrik dalam keadaan akueus? A Silver nitrate C Calcium sulphate Argentum nitrat Kalsium sulfat B Sodium chloride D Barium sulphate Natrium klorida Barium sulfat Aras sederhana

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An aqueous solution of silver nitrate solution, 0.2 mol dm-3 is electrolysed using carbon electrodes. What will be formed at the cathode and anode? Larutan argentum nitrat akueus 0.2 mol dm-3 dielektrolisiskan menggunakan elektrod karbon. Apakah yang akan terhasil di katod dan di anod? Cathode katod A B C D

Anode anod

Hydrogen gas Gas hidrogen Oxygen gas Gas oksigen Silver Argentum Silver Argentum

Oxygen gas Gas oksigen Hydrogen gas Gas hidrogen Oxygen gas Gas oksigen Nitrogen dioxide gas Gas nitrogen dioksida Aras sederhana

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ELEKTROKIMIA [Elektrolisis Sebatian Akues] BAB 6 7

Which of the following are true about electrolysis of dilute sulphuric acid using carbon electrodes? Antara berikut, yang manakah benar mengenai elektrolisis asid sulfurik cair menggunakan elektrod karbon? I II III IV

A B

The concentration of sulphuric acid decreases Kepekatan asid sulfurik berkurang The ratio of hydrogen gas to oxygen gas produced is 2:1 Nisbah gas hidrogen kepada gas oksigen yang terhasil ialah 2:1 The hydrogen ions are discharged to form hydrogen gas Ion hydrogen ternyahcas untuk membentuk gas hidrogen The solution becomes less acidic Larutan menjadi kurang berasid I and II I dan II I and IV I dan IV

C D

II and III II dan III II and IV II daan IV Aras sederhana

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Which of the following electrolytes when electrolyses will yield the same products as sodium nitrate solution using platinum electrodes? Antara elektrolit berikut,apabila dielektrolisiskan memberi hasil yang sama seperti larutan natrium nitrat dengan menggunakan elektrod platinum ? A Silver nitrate solution C Zinc fluoride solution Larutan argentum nitrat Larutan zink fluorida B Copper(II) nitrate solution D Magnesium iodide solution Larutan kuprum(II) nitrat Larutan magnesium iodida Aras tinggi -3 Diagram 8 shows the electrolysis of 0.1 mol dm sodium nitrate solution? Rajah 8 menunjukkan elektrolisis 0.1 mol dm-3 larutan natrium nitrat?

Diagram 8 Rajah 8

A B C D

2NO34OH4OH2NO3-

→ → → →

Anode Anod 2NO2 + O2 + 2eO2 + 2H2O + 4eO2 + 2H2O + 4e2NO2 + O2 + 2e-

2H+ + 2H+ + Na+ + Na+ +

2e2eee-

Cathode katod → H2 → H2 → Na → Na Aras sederhana

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ELEKTROKIMIA [Elektrolisis Sebatian Akues] BAB 6 10

Diagram 9 shows the electrolysis of a concentrated solution Y. Rajah 9 menunjukkan electrolysis satu larutan pekat, Y.

Diagram 9 Rajah 9 Which of the following is Y? Antara berikut, yang manakah Y? A Sodium nitrate solution Larutan natrium nitrat B Copper(II) sulphate solution Larutan kuprum(II) sulfat

C D

Silver nitrate solution Larutan argentum nitrat Potassium chloride solution Larutan kalium klorida Aras tinggi

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When aqueous copper(II) sulphate solution is electrolysed using copper electrodes, the half equation of the reaction that occurs at the anode is Apabila larutan kuprum(II) sulfat dilektrolisiskan menggunakan elektrod-elektrod kuprum, setengah persamaan bagi tindak balas yang berlaku di anod ialah A B C D

2H+ + 2e- → H2 4OH- → O2 + 2H2O 2+ Cu + 2e- → Cu Cu → Cu2+ + 2e-

+ 4e-

Aras sederhana 12

Diagram 11 shows the electrolysis of silver nitrate solution using silver electrodes. Rajah 11 menunjukkan elektrolisis larutan argentum nitrat menggunakan elektrod argentum.

Diagram 11 Rajah 11

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ELEKTROKIMIA [Elektrolisis Sebatian Akues] BAB 6 Which half equation represents the reactions at the cathode and anode? Setengah persamaan manakah yang mewakili tindak balas di katod dan anod?

A B C D

Anode Anod + Ag → Ag + eAg → Ag+ + e4OH- → O2 + 2H2O 4OH → O2 + 2H2O

Ag+ + 2H+ + Ag+ + 2H+ +

+ 4e+ 4e-

Cathode Katod e → Ag 2e → H2 e- → Ag 2e → H2 Aras sederhana

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Copper(II) sulphate solution is electrolysed using copper electrodes What can be observed at the anode and the cathode after 30 minutes?. Larutan kuprum(II) sulfat dielektrolisiskan dengan menggunakan elektrod kuprum. Apakah yang dapat diperhatikan pada anod dan katod selepas 30 minit?

A B C D

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Anode Anod Copper plate becomes thinner Plat kuprum menjadi nipis Copper plate becomes thinner Plat kuprum menjadi nipis Copper plate becomes thicker Plat kuprum menjadi tebal Gas bubbles are released Gelembung gas terbebas

Cathode Katod Copper plate becomes thicker Plat kuprum menjadi tebal Gas bubbles are released Gelembung gas terbebas Copper plate becomes thinner Plat kuprum menjadi nipis Copper plate becomes thicker Plat kuprum menjadi tebal Aras sederhana

During electrolysis of silver nitrate solution using carbon electrodes, ions attracted to the anode are Semasa elektrolisis larutan argentum nitrat menggunakan elektrod karbon, ion-ion yang tertarik ke anod ialah A Silver ions only C Hydrogen and silver ions Ion-ion argentum sahaja Ion-ion hidrogen dan argentum B Nitrate ions only D Hydroxide and nitrate ions Ion-ion nitrat sahaja Ion-ion hidroksida dan nitrat Aras sederhana

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