Part A Use the table of standard reduction potentials given above to calculate t
ID: 925805 • Letter: P
Question
Part A
Use the table of standard reduction potentials given above to calculate the equilibrium constant at standard temperature (25 C) for the following reaction:
Fe(s)+Ni2+(aq)Fe2+(aq)+Ni(s)
Part B
Calculate the standard cell potential (E) for the reaction
X(s)+Y+(aq)X+(aq)+Y(s)
if K = 8.59×103.
Reduction half-reaction E (V) Ag+(aq)+eAg(s) 0.80 Cu2+(aq)+2eCu(s) 0.34 Sn4+(aq)+4eSn(s) 0.15 2H+(aq)+2eH2(g) 0 Ni2+(aq)+2eNi(s) 0.26 Fe2+(aq)+2eFe(s) 0.45 Zn2+(aq)+2eZn(s) 0.76 Al3+(aq)+3eAl(s) 1.66 Mg2+(aq)+2eMg(s) 2.37Explanation / Answer
Part A.
Ecell = -0.26 - (-0.45) = 0.19 V
-RTlnKeq = -nFEcell
with,
T = 25 + 273 = 298 K
Keq = equilibrium constant
we get,
8.314 x 298 x lnKeq = 2 x 96485 x 0.19
Keq = 2.67 x 10^6
Part B.
Given K = 8.59 x 10^-3
RTlnK = nFEcell
8.314 x 298 ln (8.59 x 10^-3) = 1 x 96485 Ecell
Ecell = -0.122 V