Electrochemistry – MCQ’s

Electrochemistry – MCQ’s

1. Symbol of hydronium ion is:

(a) H⁺

(b) OH^–

(c) H₃O⁺                   ✓

(d) none of these

2. An example of non electrolyte is:

(a) Glucose                 ✓

(b) aq NaCl

(c) HCl

(d) H₂SO₄

3. An example of weak electrolyte is :

(a) HNO₃

(b) HCl

(c) H₂SO₄

(d) H₂CO₃  ✓

4. During electrolysis _____ takes place at anode.

(a) Catenation

(b) oxidation  ✓

(c) reduction

(d) addition

5. Which is not the characteristic of electrolyte?

(a) Cheap

(b) conductor

(c) easily oxidized  ✓

(d) soluble in water

6. In dry cell ___acts as cathode:

(a) Zn cup

(b) graphite rod  ✓

(c) paste

(d) steel rod

7. In Zn-Cu galvanic cell, Zn is dipped in:

(a) ZnSO₄  ✓

(b) Zn(NO₃)₂

(c) CuSO₄

(d) both a & b

8. In Zn-Cu galvanic cell, Zn is used as:

(a) Cathode

(b) anode  ✓

(c) electrode

(d) all of above

9. In Zn + Cu⁺² Zn⁺² + Cu, Zn is:

(a) Oxidized  ✓

(b) reduced

(c) redoxed

(d) decomposed

10. Anions are ________ions.

(a) Positive

(b) neutral

(c) negative  ✓

(d) amphoeteric

11. Cations are _______ ions.

(a) Negative

(b) positive  ✓

(c) neutral

(d) none of these

12. Electrolysis of NaCl is done in the cell:

(a) Electrolytic

(b) voltaic

(c) down’s  ✓

(d) faradays’

13. Which one is not produced during electrolysis of aqueous NaCl?

(a) Na⁺

(b) OH^–

(c) H₂O  ✓

(d) Cl^–

14. In pure water, out of ____only one molecule ionizes.

(a) 6 × 10⁶

(b) 6 × 10⁸  ✓

(c) 6 × 10¹⁶

(d) 6 × 10¹²

15. Which one is weak electrolyte?

(a) Citric acid

(b) carbonic acid

(c) tartaric acid

(d) all of these  ✓

16. Metallic, ammonium and hydrogen ions carry _____charges.

(a) Negative

(b) neutral

(c) positive  ✓

(d) partial positive

17. Electrode through which electrons enter the external circuit:

(a) Anode  ✓

(b) Cathode

(c) electrode

(d) none of these

18. Electrode through which electrons leave the external circuit:

(a) Anode

(b) Cathode  ✓

(c) graphite

(d) electrolyte

19. Which one is conductor?

(a) Naphthalene

(b) paraffin wax

(c) plastic

(d) HCl  ✓

20. Which solution is not a conductor:

(a) NaCl

(b) Kl

(c) CO (NH₂)₂  ✓

(d) CuCl₂

21. Rods through which electric current enters or leaves the cell:

(a) Protons

(b) electrons

(c) electrodes  ✓

(d) all of these

22. Spontaneous redox reaction produce current in:

(a) Voltaic cell

(b) electrolytic cell

(c) galvanic cell

(d) Both a & b  ✓

23. In an oxidation reaction electrons are:

(a) Absorbed

(b) lost  ✓

(c) moved

(d) increased

24. In reduction reaction electrons are:

(a) Lost

(b) absorbed  ✓

(c) kept constant

(d) all of these

25. Which of the following is a good electrolyte?

(a) NaCl

(b) H₂SO₄

(c) NaOH

(d) All of these  ✓

26. Which ionizes in small extent in water

(a) Ca(OH)₂  ✓

(b) NaCl

(c) NaOH

(d) H₂SO₄

27. Oxidation always takes place at

(a) Anode  ✓

(b) Cathode

(c) Both of them

(d) Nome of them

28. Who invented first electrolytic cell?

(a) Berzelius

(b) Volta  ✓

(c) J. Dalton

(d) Newton

29. In galvanic cell, cathode carries.

(a) Positive charge  ✓

(b) Negative charge

(c) No charge

(d) Neutral charge

30. Cl₂ gas is formed, when Cl^– ions are

(a) Reduced

(b) Oxidized  ✓

(c) Removed

(d) Reacted with metals

31. Which ion is not formed during is of aqueous sodium chloride?

(a) H⁺  ✓

(b) H₂

(c) Cl₂

(d) NaOH

32. Which medium accelerates the process of rusting?

(a) Acidic  ✓

(b) Basic

(c) Buffer

(d) Neutral

33. Stainless steel contains

(a) Nickel

(b) Iron

(c) Chromium

(d) All of these  ✓

34. Which of the followings is a corrosion resistant metal?

(a) Fe

(b) Zn

(c) Sn  ✓

(d) Sr

35. The electrolytic cell is made up of

(a) Cement

(b) Glass

(c) Wood

(d) All of these  ✓

36. Which of the following is a common example of silver plating?

(a) Wares

(b) Cutlery

(c) Jewellery

(d) All of these  ✓

37. Which metal has a great tendency to corrosion?

(a) Silver

(b) Copper

(c) Aluminum  ✓

(d) All of these

38. Chemical formula of sodium thio-sulphate is

(a) Na₂SO₄

(b) Na₂SO₃

(c) Na₂S₂O₃  ✓

(d) NaSO₄

39. Sterling silver is an alloy of silver and

(a) Iron

(b) Copper  ✓

(c) Chromium

(d) Aluminum

40. In HCl, oxidation number of H is

(a) –1

(b) +1  ✓

(c) +2

(d) –2

41. The oxidation number of all elements in free state is

(a) One

(b) Two

(c) Three

(d) Zero  ✓

42. The oxidation number of Group-I elements is

(a) +1  ✓

(b) +2

(c) +3

(d) +4

43. The oxidation number of hydrogen in metal hydrides is

(a) +1

(b) –1  ✓

(c) +2

(d) –2

44. The oxidation number of oxygen is +2 in

(a) H₂O

(b) OF₂  ✓

(c) Na₂O

(d) HNO₃

45. The oxidation number of sulphur in H₂SO₄ is

(a) +1

(b) +4

(c) +6  ✓

(d) +8