Solutions to exercises
289
Partial oxidation of methane
CH 4 + 2
1
O 2 m CO + 2H 2
in the presence of iron as catalyzer, followed by the reaction
CO + H 2 O m CO 2 + H 2
catalyzed by Fe 2 (CO 3 ) 2 , Cr 2 (CO 3 ) 3, …
The balanced reaction equation is
CH 4 + H 2 O + 2
1
O 2 m CO 2 + 3H 2
2 Electrolysis of water
The overall reaction is
H 2 O m H 2 + 2
1
O 2
H 2 and O 2 are produced at the cathode and anode, respectively. The electrolytes may be liquids or solids.
2 Other procedures
Thermal disassociation of H 2 O, photochemical disassociation of H 2 O,
oxidation of reducing metal, bioproduction by using enzymes, …
4. a. Figure 117 shows schematically the curve describing the potential difference ΔE and the power density as a function of current density that it
delivers.
¨( WK
¨(
¨(>9@
3>:FP
<
@
3
¨( 3 PD[
3 PD[
L 3 PD[
L>$FP
<
@
,
, ,
,,,
Figure 117 – Form of potential difference ΔE
and power density as a function of the current density.