Electrochemistry  MCQs

MCQs of Electrochemistry

Showing 51 to 60 out of 158 Questions
51.
One Daniell cell contains 1 M ZnSO4 and 1 M CuSO4 solutions in anode and cathode half cells respectively. Another Daniell cell contains 2 M ZnSO4 and 2 M CuSO4 solutions in anode and cathode half cells respectively. if their standard cell potentials are respectively E1 and E2 V, then _____ .
(a) E1 = 2E2
(b) E2 = 2E1
(c) E2 = 4E1
(d) E1 = E2
Answer:

Option (d)

52.
What are the conditions for the reaction to be spontaneous in an electrochemical cell ?
(a) cell > 0, ΔG° > 0, KC < 1
(b) cell > 0, ΔG° < 0, KC = 1
(c) cell > 0, ΔG° < 0, KC > 1
(d) cell < 0, ΔG° > 0, KC = 0
Answer:

Option (c)

53.
Represent the cell formed by combination of copper half cell with hydrogen electrode. E°Cu2+ Ι Cu = 0.34 V;
(a) Cu Ι Cu2+(1 M) ΙΙ H+(1 M)ΙH2(1 bar)Ι Pt
(b) Pt Ι H2(1 bar) ΙΙ H+(1 M)ΙCu2+(1M)Ι Cu
(c) Pt Ι H2 Ι H+(1 M) ΙΙ CuΙ Cu2+(1M)
(d) Cu(s) Ι Cu2+(1 M) ΙΙ H2(g)Ι Pt Ι 2H+(1 M)
Answer:

Option (b)

54.
Which of the following reaction occurs at cathode during the discharging of lead storage cell ?
(a) PbSO4 + 2e- → Pb + SO42-
(b) PbSO4(s)+ 2H2O→ PbO2 + 4H+ + SO42-
(c) PbO2(s)+ 4H+(aq)+ SO42-(aq) + 2e-→ PbSO4(S) + 2H2
(d) None of these
Answer:

Option (c)

55.
For the cell reaction :

Cu2+(aq)+ Zn(s) →Zn2+(aq) +Cu(s) 

(C1)                          (C2)              

free energy change (ΔG) is a function of which ?

(a) ln(C1 + C2)
(b) lnC1C2
(c) lnC2C1
(d) lnC1
Answer:

Option (b)

56.
Which of the following reaction is not possible ?
(a) 2KBr + Cl2 → 2KCl + Br2
(b) 2Kl + Br2 → 2KBr + l2
(c) 2KBr + l2 → 2Kl + Br2
(d) 2H2O+ 2F2 → 4HF + O2
Answer:

Option (c)

57.
emf of the cell

Zn Ι ZnSO4(0.01 M) ΙΙ CuSO4(1.0 M) Ι Cu is E1.When concentration of ZnSO4 is 1.0 M, and that of CuSO4 is kept 0.01 M. The emf is E2. What is the relation between E1 and E2 ?

(a) E1 > E2
(b) E1 < E2
(c) E1 = E2
(d) E2 = 0 ≠ E1
Answer:

Option (a)

58.
Which of the following option is correct for the calculation of Λ°CH3COONa with the help of Λ°CH3COONa and Λ°HCl ?
(a) λ°Cl-
(b) Λ°NaCl
(c) λ°H+
(d) Λ°ClCH2COOH
Answer:

Option (b)

59.
Calculate Ecell for the following cell.

AgΙ Ag+(0.01 M) ΙΙ Ag+(0.1 M) Ι Ag ;
Ag+ΙAg = 0.80 V

(a) E°cell = 0.80 V
(b) E°cell = 0.0296 V
(c) Cell will not work as both electrodes are same
(d) E°cell = 0.059 V
Answer:

Option (d)

60.
What is cell potential of the following cell.

E°(Cr3+ΙCr) = -0.72V and

E°(Fe2+ΙFe) = -0.42V

Cr Ι Cr3+(0.1 M) ΙΙ Fe2+(0.01 M) Ι Fe

(a) -0.26V
(b) 0.26V
(c) 0.339V
(d) -0.339V
Answer:

Option (b)

Showing 51 to 60 out of 158 Questions