2020 Group work-3 [3-11 Deduce Iny=-Az, Z_VI from In, =-AZVT [3-2 Write the electrode reactions of the following electrodes and indicate which kind of electrode they belong to: (1)Pb(s)IPbO2(s)I PbSO4(s)IH+, SO42-(the positive electrode in lead-acid battery) (2)Hg(I?SOA(s)I CaSO4(s)I Ca2+(an electrode was once used for determining the Mn+. ht (4)Ni(s)I Ni(OOH(S)INi(OH)(s)IOH-(m)(the positive electrode in a Ni-Cd or Ni-H battery) [3-3 Design the following reactions into reversible electrochemical cells (1)Pb(s)+ H2SO4(m)=PbSO4(s)+ H2(g)(a replacement reaction) (2)H(m+ oh-(m2)=H2o((the neutralization reaction) (3)Ni(m1)+ 2H20()-Ni(OH)(S)+2H*(m2)(a hydration reaction) (4)HCI(m1)==HCl(m2)(concentration difference)Which is higher for a galvanic cell, mI or m2? (5)H2(P1)==H2(p2)(difference in partial pressure)Which is higher for a galvanic cell, Pi or P2? [3-4] Write out the half-reaction and cell reaction of the following cells: (1)Pb(s)Pbo(s)oH-(c)HgO(s)Hg() (2)Pt(s), H2(g, p )HCI(m)AgCI(s)-Ag(s) (3)Ag(s)-AgCl(s)KCI(m)Hg2 CI(s)-Hg() (4)Pt(s), H2(g, pe)KoH(aq)HgO(s)-Hg()
2020 Group work-3 【3-1】Deduce ln A Z Z I + − = − from 2 i i ln = −AZ I . 【3-2】Write the electrode reactions of the following electrodes and indicate which kind of electrode they belong to: (1) Pb(s)PbO2 (s)PbSO4(s)H+ , SO4 2− (the positive electrode in lead-acid battery) (2) Hg(l)Hg2SO4(s)CaSO4(s)Ca2+ (an electrode was once used for determining the concentration of Ca2+) (3) Pt(s) MnO4 − , Mn2+, H+ (4) Ni(s)Ni(OOH)(s)Ni(OH)2(s)OH− (m) (the positive electrode in a Ni-Cd or Ni-H battery) 【3-3】Design the following reactions into reversible electrochemical cells: (1) Pb(s) + H2SO4(m) == PbSO4(s) + H2(g) (a replacement reaction) (2) H+ (m1) + OH− (m2) == H2O (l) (the neutralization reaction) (3) Ni2+(m1) + 2H2O(l) == Ni(OH)2(s) + 2H+ (m2) (a hydration reaction) (4) HCl(m1) == HCl(m2) (concentration difference) Which is higher for a galvanic cell, m1 or m2? (5) H2(p1) == H2(p2) (difference in partial pressure) Which is higher for a galvanic cell, p1 or p2? 【3-4】Write out the half-reaction and cell reaction of the following cells: (1) Pb(s)|PbO(s)|OH– (c)|HgO(s)|Hg(l) (2) Pt(s), H2 (g, p )|HCl(m) |AgCl(s)-Ag(s) (3) Ag(s)-AgCl(s)|KCl(m)|Hg2Cl2(s)-Hg(l) (4) Pt(s), H2(g, p )|KOH(aq)|HgO(s)-Hg(l)