Well structured WBBSE Class 10 Physical Science MCQ Questions Chapter 8.3 Electricity and Chemical Reactions can serve as a valuable review tool before exams.
Electricity and Chemical Reactions Bonding Class 10 WBBSE MCQ Questions
Multiple Choice Questions :
Question 1.
The electrolyte is
(A) Glycerine
(B) Sugar
(C) Sodium chloride
(D) Glucose
Answer:
(C) Sodium chioride
Question 2.
The vessel in which electrolysis takes place is called :
(A) Voltameter
(B) Voltmeter
(C) Calorimeter
(D) Ammeter
Answer:
(A) Voitameter
Question 3.
Which of the following substances is non-metal but conductor :
(A) Nickel
(B) Iron
(C) Silver
(D) Gas carbon
Answer:
(D) Gas carbon
Question 4.
A silver substance is to be gold plated which is to be used as anode:
(A) Pt
(B) Au
(C) Cu
D) Fe
Answer:
(B) Au
Question 5.
What is the volume ratio of produced hydrogen and oxygen from electrolysis of water ?
(A) 1 : 2
(B) 2 : 1
(C) 2 : 3
(D) 1 : 1
Answer:
(B) 2 : 1
Question 6.
Which agent conducts electricity during electrolysis ?
(A) water
(B) ion
(C) atom
(D) molecule.
Answer:
(B) ion
Question 7.
Molter sodium chloride conducts electricity due to the presence of:
(A) free electrons
(B) free ions
(C) free molecules
(D) atoms of sodium and chlorine
Answer:
(B) free ions
Question 8.
An electrolyte :
(A) gives ions only when dissolved in water
(B) gives ions only when electric current is passed
C) has ions even in the solid state
(D) does not give complex ions in solution
Answer:
(C) has ions even in the solid state
Question 9.
The amount of an ion discharged during electrolysis is not directly proportional to:
(A) resistance
(B) time
(C) current
(D) chemical equivalent
Answer:
(A) resistance
Question 10.
Which one of the following solutions will conduct electricity ?
(A) Magnesium chloride in water
(B) Sugar in water
(C) Sugar in ethyl alcohol
(D) lodine in ethyl alcohol
Answer:
(A) Magnesium chloride in water
Question 11.
In the electrolysis of NaCl :
(A) Cl– ion is oxidised at anode
(B) Cl– ion is reduced at anode
(C) Cl– ion is oxidised at cathode
(D) Cl– ion is neither reduced or oxidised
Answer:
(A) Cl– ion is oxidised at anode
Question 12.
On the electrolysis of aQuestion solution of sodium sulphate, on cathode, we get :
(A) Na
(B) H2
(C) SO2
(D) SO3
Answer:
(A) Na
Question 13.
On electrolysis a solution of dilute H2 SO4 using platinum electrodes, the gas evolved at the anode is :
(A) SO2
(B) SO3
(C) O2
(D) H2
Answer:
(C) O2
Question 14.
When a copper wire is placed in solution of AgNO3, the solution acquires blue colour. This is due to the formation of:
(A) Cu+2 ions
(B) Cu+ ions
(C) soluble complex of copper with AgNO3
(D) none of these
Answer:
(A) Cu+2 ions
Question 15.
Flow of current in an electrolyte is due to :
(A) atoms
(B) electrons
(C) ions
(D) none of these
Answer:
(C) ions
Question 16.
Use of electrolysis is :
(A) Electroplating
(B) Electrorefining
(C) Both A And B
(D) none of these
Answer:
(C) Both A And B
Question 17.
Electroplating was discovered by :
(A) Faraday
(B) Arrhenius
(C) Newton
(D) Dalton
Answer:
(A) Faraday
Question 18.
Which of the following is a strong electrolyte :
(A) Ca(NO3)2
(B) HCN
(C) H2 SO3
(D) NH4 OH
Answer:
(A) Ca(NO3)2
Question 19.
The electroplating with chromium is under taken because :
(A) electrolysis of chromium is easier
(B) chromium can form alloys with other metals
C) chromium gives a protective and decorative coating to the base metal
(D) of high reactivity of chromium metal
Answer:
(C) Chromium gives a protective and decorative conting to the base metal.
Question 20.
Pure water does not conduct electricity because it:
(A) has low boiling point
(B) is neutral
(C) is almost unionised
(D) is readily decomposed
Answer:
(C) is almost unionised
Question 21.
During electrolysis of CuSO4, the product collected at the anode is:
(A) Oxygen
(B) Hydrogen
(C) Copper
(D) Sulphate
Answer:
(A) Oxygen
Question 22.
During the electrolysis of fused sodium chloride, the anodic reaction is :
(A) reduction of sodium ions
(B) oxidation of sodium ions
(C) reduction of chloride ions
(D) oxidation of chloride ions
Answer:
(D) oxidation of chloride ions
Question 23.
The unit of quantity of electricity is :
(A) volt
(B) coulomb
(C) ampere
(D) ohm
Answer:
(B) coulomb
Question 24.
In electroplating copper with silver, the both solution used is of K[Ag(CN)2] instead of AgNO3 because on account of complex formation :
(A) a thin coating of silver is obtained
(B) Ag+ ions are completely removed from the solution
C) expenses on electricity are reduced
(D) availability of Ag+ ions in solution is so reduced that they are not replaced by copper ions.
Answer:
(D) availability of Ag+ ions in solution is so reduced that they are not replaced by copper ions.
Question 25.
For the electroplating of nickel, nickel sulphate is mixed with :
(A) water
(B) nitric acid
(C) boric acid
(D) H2 SO4 as electrolyte
Answer:
(C) boric acid
Question 26.
During electrolysis of copper using copper electrodes of copper in solution is :
(A) increased
(B) decreased
(C) unaltered
(D) None of these
Answer:
(C) unaltered
Question 27.
Which one of the following is a non-electrolyte ?
(A) NaCl
(B) HCl
(C) urea
(D) H2 SO4
Answer:
(C) urea
Question 28.
Which one is a strong electrolyte ?
(A) NaOH
(B) NH4 OH
(C) CH3 COOH
(D) glucose
Answer:
(A) NaOH
Question 29.
In electrolytic solution electricity is conducted by :
(A) electrons
(B) atoms
(C) ions
(D) molecules
Answer:
(C) ions
Question 30.
Electrolysis of CuSO4 solution using Cu-electrodes, the products at electrodes are :
(A) Cu-at anode
(B) Cu+2 at anode
(C) H2 at cathode
(D) O2 at anode
Answer:
(B) Cu+2 at anode
Question 31.
Reaction takes place during electrolysis at electrodes are :
(A) oxidation at cathode
(B) reduction at anode
(C) reduction at cathode
(D) no chemical reaction
Answer:
(C) reduction at cathode
Question 32.
Which one is an inert electrode?
(A) copper
(B) iron
(C) platinum
(D) graphite
Answer:
(D) graphite
Question 33.
During the electroplating of a spoon with silver, the reaction taking plac at anode is.
(A) Ag+2+2e → Ag
(B) Ag-2 e → Ag+2
(C) Ag-e → Ag+
(D) Ag++ e → Ag
Answer:
(C) Ag-e → Ag+
Question 34.
The reaction that takes place at anode is :
(A) oxidation
(B) reduction
(C) substitution
(D) acid-base
Answer:
(A) oxidation
Question 35.
Which of the following is a weak electrolyte?
(A) CuSO4
(B) KOH
(C) H2 SO4
(D) CH3 COOH
Answer:
(D) CH3 COOH
Question 36.
Identify the strong electrolyte
(A) ammonium hydroxide
(B) acetic acid
(C) nitric acid
(D) carbonic acid
Answer:
(C) nitric acid
Question 37.
Choose the wrong statement :
(A) Pure water is a poor conductor of electricity
(B) Cations carry positive charges
(C) Anions move towards anode during electrolysis
(D) Oxidation takes place at the cathode
Answer:
(D) Oxidation takes place at the cathode
Question 38.
11.2 L of a gas is evolved at cathode during electrolysis of water. Amount of gas evolved at anode at the same temperature and pressure is :
(A) 5.6 L
(B) 11.2 L
(C) 22.4 L
(D) 44.8 L
Answer:
(A) 5.6 L
Question 39.
During copper refining which is used as anode?
(A) platinum
(B) pue copper
(C) graphite
(D) impure copper
Answer:
(D) impure copper
Question 40.
Energy conversion during electrolysis is :
(A) chemical to electrical
(B) electrical to chemical
(C) electrical to mechanical
(D) mechanical to electrical
Answer:
(B) electrical to chemical
Fill in the blanks :
1. _______ is a vessel in which electrolysis is carried out.
Answer:
Voltameter.
2. In electrolysis of water, hydrogen accumulates at the cathode and _______ at the anode.
Answer:
oxygen.
3. The decomposition process of electrolytes into ions is known as _______ dissociation.
Answer:
ionic.
4. In electrolyte electrical conduction occurs by migration of _______.
Answer:
ions.
5. An electrolyte is a compound that conducts electricity in fused or solution state and at the same time _______ chemically.
Answer:
decomposes.
6. In the electrolysis, electric current enters the electrolyte solution through the anode and leaves through the _______.
Answer:
cathode.
7. Aluminium is extracted by the electrolysis of a molten mixture of bauxite and _______.
Answer:
cryolyte.
8. In the electrolysis of water, it is found that at the same temperature and pressure _______ olume of oxygen and two volumes of hydrogen are evolved.
Answer:
one.
9. Compounds which in the _______ state or in aqueous solution can conduct electricity and are decomposed chemically yielding new substances are called electrolytes.
Answer:
fused.
10. Mercury is a good conductor of electricity but is not an _______.
Answer:
electrolyte.
11. Rubber is _______ of electricity.
Answer:
non-conductor.
12. In electro-plating, the plating metal is used as _______.
Answer:
cathode.
13. The process of depositing a thin layer of one metal over another metal with the help of an electric current is called _______.
Answer:
electroplating.
14. _______ is a semi-conductor.
Answer:
Silicon.
15. 2 H⊕ + 2 e →
Answer:
2 H.
16. The aqueous solution of sugar is _______.
Answer:
non-electrolyte.
17. _______ is used as an electrolyte for the electroplating of Nickel.
Answer:
Nickel sulphate (NiSO4) with boric acid (H3 BO3)
18. The aqueous solution of sodium hydroxide is _______.
Answer:
electrolyte.
19. In electrolysis _______ conduct electricity.
Answer:
ions.
20. Between H⊕ and Al3+ _______ ion is discharged first at cathode.
Answer:
H⊕.
21. Between Br and OH– _______ ion is discharged first at anode.
Answer:
OH–
22. Compounds which do not conduct an electric current is aqueous solution or in the molten state are termed as_______.
Answer:
non-electrolytes.
23. The _______ of the total number of molecules of an electrolyte dissociating into free ions is known as the degree of dissociation.
Answer:
fraction.
24. The products formed during electrolysis are deposited or liberated only at the _______.
Answer:
electrodes.
25. _______ changes that occur during electrolysis at the electrodes start as soon as the current is switched on and cease as soon as it is switched off.
Answer:
Chemical.
26. Electrolysis of molten NaCl produces and at cathode _______ and _______ anode respectively.
Answer:
Na, Cl2
27. With increase of temperature of the electrolytic solution its conductivity will _______.
Answer:
increase
28. Example of strong electrolyte is _______.
Answer:
H2 SO4
29. It is the _______ which are responsible for conduction of electricity in electrolytic solution.
Answer:
ions
30. In electroplating with gold the anode used is _______.
Answer:
pure gold plate.
31. During gold plating, the objects to be coated with gold are used as _______.
Answer:
cathode
32. During silver plating the electrolyte used is _______.
Answer:
potassium argentocyanide
33. In case of metals, current is carried by _______.
Answer:
electrons
34. In case of aqueous solution of an electrolyte, current is carried by _______.
Answer:
ions
35. In case of _______ electrolyte, it dissociates completely when dissolved in water.
Answer:
strong
36. In case of _______ electrolyte, it dissociates partially when dissolved in water.
Answer:
weak
37. _______ is connected to the positive terminal of the battery.
Answer:
Anode
38. _______ is connected to the negative terminal of the battery.
Answer:
cathode
39. During electrolysis of a mixture of alumina and cryolite _______ is used to lower the melting point of pure alumina.
Answer:
fluorspar
40. During electrolysis of copper sulphate using copper electrodes, the weight of anode _______.
Answer:
decreases
State whether the following statement is True or False : VSA
1. Little amount of acid is added to water during electrolysis of water.
Answer:
True
2. Through electroplating, a layer of high reactive metal is applied over a low reactive metal is applied over a low reactive metal.
Answer:
False
3. During electrolysis electrolytes conduct electricity through electrons.
Answer:
False
4. Method of electrolysis is utilized during extraction of metals such as aluminium, sodium etc.
Answer:
True
5. During electrolysis of water, hydrogen and Oxygen gas are produced at a volume ratio of 1: 2
Answer:
False
6. Pure water is a good conductor of electricity.
Answer:
False
7. Sodium chloride can conduct electricity in molten state.
Answer:
True
8. During electrolysis, Oxidation takes place at cathode and reduction takes place at anode.
Answer:
False
9. When an electrolyte is dissolved in water, ions ae formed.
Answer:
True
10. When an electrolyte is dissolved in water, ions are formed, hence the solution becomes charged.
Answer:
True