Question

1)Calculate forthe electrochemical cell below,

Pb(s) |PbSO4(s) | Pb2+(aq) Ag+(aq) | Ag(s)

given the following standard reduction potentials.

Ag+(aq) + e- ->Ag(s) E° = +0.799 V

PbSO4(s)+ 2e- -> Pb(s) + SO4 2-(aq) E = -0.356 V

a) -1.954 V

b) -1.155 V

c) +0.443V

d) +1.155 V

2) Consider the following half- reactions:

Cu2+ (aq) + 2e- --> Cu(s)E = +0.34 V

Sn2+(aq) + 2e- --> Sn(s) E = -0.14 V

Fe2+(aq) +2e- --> Fe(s)E = -0.44 V

Al3+(aq) +3e- --> Al(s) E = -1.66 V

Mg2+(aq) + 2e---> Mg(s) E = -2.37 V

Which of the abovemetals or metal ions will reduce Fe2+ ?

a) Cu(s) andSn(s)

b) Cu2+(aq) andSn2+(aq)

c) Al3+(aq) andMg2+ (aq)

d) Al(s) andMg(s)

e) Sn(s) and Al3+(aq)

3) The following reaction occurs spontaneously

2H+ (aq) +Ca(s) --> Ca2+(aq) + H2(g)

Write a balanced recuction half-reaction-

a) 2H+(aq) + 2e --> H2(g)

b) 2H+ (aq) --> H2(g) + 2e-

c) H2(g) --> 2H+(aq) + 2e-

d) Ca(s) + 2e- --> Ca2+(aq)

e) Ca(s) --> Ca2+(aq) + 2e-