Mc Ques Eng Chemical Cells

CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

Public Exam Questions :

Directions : Question 1 and question 2 refer to the following diagram :

1. Which of the following metals, when used as electrode X, would produce the largest reading on the voltmeter? A. Iron B. Lead C. Magnesium D. Zinc 2. If the electrode X is zinc, which of the following statements concerning the cell is INCORRECT? A. Electrons flow from electrode X to the copper electrode in the external circuit. B. Chlorine is given off at electrode X. C. Hydrogen is given off at the copper electrode. D. The mass of electrode X gradually decreases. (HKCEE 1985)

3.

Referring to the above diagram, the largest current flowing from iron to metal X in the external circuit can be obtained when X is A. copper B. magnesium -1–

CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

C. silver D. zinc (HKCEE 1987)

4. The anode of a dry cell is usually made of A. zinc B. iron C. tin D. lead (HKCEE 1989)

5. Which of the following pairs of metals would be expected to give the largest voltage when they are used as electrodes in a simple chemical cell using potassium nitrate solution as the electrolyte? A. Zn and Pb B. Mg and Ag C. Pb and Cu D. Fe and Mg (HKCEE 1990)

6.

Which of the following combinations would produce the largest current flowing from metal X to metal Y in the external circuit? Metal X Metal Y A. Fe Cu B. Mg Ag C. Ag Zn D. Cu Pb (HKCEE 1991)

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CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

Directions : Question 7 and question 8 refer to the following diagrams :

7. Which of the following represents the correct order of increasing reactivity of the metals P, Q, R and S? A. R, P, Q, S B. Q, P, R, S C. P, Q, S, R D. P, R, S, Q 8. Which of the two metals used as electrodes would give the largest cell voltage? A. Q and R B. Q and S C. S and R D. S and P (HKCEE 1992)

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CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

9.

With reference to the above diagram, which of the following statements is correct? A. The electrode made of metal X is the positive pole. B. Copper is at a higher position in the electrochemical series than metal X. C. The mass of the copper electrode decreases. D. The mass of the electrode made of metal X decreases. (HKCEE 1993)

10. Which of the following statements concerning a silver oxide cell is/are correct? (1) The cell is rechargeable. (2) The cell can maintain a steady voltage during discharge. (3) The positive electrode of the cell is silver oxide. A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only (HKCEE 1995)

11. In the set-up shown below metal X is more reactive than metal Y.

Which of the following statements concerning this set-up is / are correct? (1) Electrolysis occurs inside the lemon. -4–

CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

(2) Chemical energy is changed into electrical energy. (3) Electrons flow from metal Y to metal X in the external circuit. A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only (HKCEE 1995)

12.

Which of the following metals would produce the smallest voltage in the above set-up? A. iron B. aluminium C. copper D. magnesium (HKCEE 1996)

Assertive-typed question 13. Statement 1 : Zinc-carbon dry cells are rechargeable. Statement 2 : The electrolyte used in the zinc-carbon dry cells is potassium hydroxide. (HKCEE 1996)

14. Consider the following chemical cell :

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CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

Which of the following changes would lead to an increase in the voltage of the cell? (1) The zinc electrode is replaced with a magnesium electrode. (2) The copper electrode is replaced with an iron electrode. (3) The sodium chloride solution is replaced with a sugar solution. A. (1) only B. (2) only C. (1) and (2) only D. (2) and (3) only (HKCEE 1999)

15. Consider the chemical cell shown below :

Which of the following statements concerning the cell is/are correct ? (1) Oxidation takes place at the copper electrode. (2) The concentration of magnesium ions in beaker X increases. (3) The salt bridge allows electrons to flow from one electrode to the other electrode. A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only (HKCEE 2000)

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CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

16. Which of the following is/are advantage(s) of using alkaline manganese cells over zinc-carbon cells in cassette players? (1) Alkaline manganese cells have longer life time. (2) Alkaline manganese cells are rechargeable. (3) Alkaline manganese cells give a more steady voltage over discharge. A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only (HKCEE 2003)

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CHEMICAL CELLS

Textbook (Book 2) : p.131 - 157

Suggested Answers :

1.

C

2.

B

3.

B

4.

A

5.

B

6.

B

11.

B

12 .

C

13 .

D

14 .

A

15 .

B

16 .

C

-8–

7.

A

8.

C

9.

D

10 .

D