Q1. During electrolysisof aqueous solution of a salt pH in the space near one of the electrodes is increased. Which of the following salt solution was electrolyzed?
(1) KCL(2) CuCl2 (3) Cu(NO3)2 (4) CuSO4

Q2. The ionic mbilityof alkali metal ions in aqueous solution is maximum for
(1) Na+ (2) K+ (3) Rb+​ (4) Li+

Q3. During the recharging of lead acid storage cell the reaction at anode is
(1) Pb​2+ coverts toPb (2)Pb​2+coverts toPb​4+ (3)Pbcoverts toPb​2+(4) Pb​4+ converts to Pb2+

Q4. Standard cell voltage for cell Pb/Pb2+||Sn2+/Snis -0.01V. If the cell is to exhibit Ecell=0, the value of log[Sn2+]/[Pb2 +] should be
(1) 0.33 (2) 0.5 (3) 1.5 (4) -0.5

Q5.The hydrogen electrode is dipped in a solution of pH = 3 at 25oC. The reduction potential of the electrode would be
(1) 0.177V (2) 0.087V (3) -0.177V (4) 0.059V

Q6. What would be the emf of the given cell?
Pt | H2(P1) | H+ (aq) | H2 (P2) |Pt​
(1) RT/ F ln P1 / P2(2)RT/ 2FlnP1/ P2 (3)RT/ FlnP2/ P1(4)RT/ 2FlnP2/ P1

a. KCl As the cation (K+) has lower electrode potential than H, hydrogen is liberated at the cathode.There is accululation of H+ at one electroded, resulting in increase in pHb. Rb+. The hydration enthalpy is in the orderLi+ > Na+ > K+ > Rb+ > Cs+As the hydration of Li+ is more, the hydrated ion atomic size is more for Li+ and less for Rb+so the mobility is faster for Rb+ and less for Li+c. Pb2+ is converted to Pb.The overall cell reaction during recharge is2PbSO4 + 2 H2O Pb + PbO2 + 2H2SO4d. The cell reaction isAt anode : Pb Pb2+ + 2e-At cathode: Sn2+ + 2e-  SnThe overall reaction isPb + Sn2+Pb2+ + Snaccording to Nernst equationE = E0 -0.0591n log Pb2+Sn2+0 = -0.01 -0.05912 log Pb2+Sn2+0 = -0.01 +0.05912 log Sn2+Pb2+0.05912 log Sn2+Pb2+ = 0.01 log Sn2+Pb2+ = 0.01 ×20.0591 = 0.3384 e. E = -0.05911 × pH = -0.05911 × 3 = -0.177 Vf. Option b is correct2H+ + 2e- H2 (P2)H2 (P1)  2H+ + 2e-overall cell reaction isH2(P1) H2(P2)E = E0 - RT2F log P2P1 = 0 -RT2F log P2P1  =RT2F log P1P2 

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