Ok one more!
Write the balanced equations and assign oxidation numbers to all atoms in these two reactions involving iron. If the effective oxidation number of any particular atom changes during the reaction then a redox reaction has occurred. If a redox reaction takes place then write the half reactions involved.
A. Solid iron (II) oxide is exposed to carbon monoxide and high heat. The process produces molten iron in the liquid state and carbon dioxide.
B. Solid FeCO3 is heated strongly to form FeO and carbon dioxide.