Answer to Question #72210 in General Chemistry for Jo

Question

Iron is a transition metal and, as such, can form two types of "oxide" compounds, FeO and Fe2O3.
(a) What's different about the iron cations in each compound?
(b) How does that difference affect the final compound formulas?
(c) Explain what happens to the electrons when iron and oxygen atoms combine to form either of these compounds.

Answer 1

A) Ion radius of Fe2+ — 0,080 nm, Fe3+ — 0,067 nm.
Fe2+and Fe3+ have different number of electrons, which in turn results in different properties of these species.

B) In its pure form, iron is a silvery-white metal, distinguished by its ability to take and retain a magnetic field, and also dissolve small amounts of carbon when molten (thus yielding steel). Commercial refining of iron is based on the heating of Fe2O3 or Fe3O4 (magnetite) with a mixture of other substances in the high temperature environment of the blast furnace. The oxides are reduced to pure iron.

C) When Fe and O2 are combined, the Fe atoms each lose an electron, forming cations, and the O2 atoms each gain an electron to form anions O2−.