Chapter 22, Problem 110FP

Various thermochemical cycles are being explored as possible sources of $H_2\left(g\right)$ . The object is to find a series of reactions that can be conducted at moderate temperatures (about $500°C$ ) and that results in the decomposition of water into $H_2$ and $O_z$ . Show that the following series of reactions meets these requirements.
$FeC{I}_2+H_{2}O\to F{e}_3{O}_4+HCI+H_2$

$F{e}_3{O}_4+HCI+C{I}_2\to FeC{I}_3+H_{2}O+O_2$

$FeC{I}_3\to FeC{I}_2+C{I}_2$