Column A
1.
The oxidation number of Fe in the compound Fe2O4 is ___________.
:
The oxidation number of Fe in the compound Fe2O4 is ___________.
2.
The oxidation number of Iron (Fe) as a free element is ___________.
:
The oxidation number of Iron (Fe) as a free element is ___________.
3.
The oxidation number of Fe in the compound FeCl3 is _______.
:
The oxidation number of Fe in the compound FeCl3 is _______.
Column B
a.+3
b.+2
c.-3
d.-1
e.+4
f.-4
g.0
h.-2
i.+1
1. The oxidation number of Fe in the compound Fe2O4 is ___________.
Before I answer this question, it's important to clarify that Fe2O4 is not a typical chemical formula for a compound with iron and oxygen. The common oxidation states of iron (Fe) are +2 and +3, and the common oxides are FeO (where Fe is +2) and Fe2O3 (where Fe is +3). There's a possibility of a mixed-valence oxide such as Fe3O4 (magnetite), which has both Fe(II) and Fe(III), but this does not correspond to Fe2O4.
If Fe2O4 was to exist with iron having the same oxidation state in all positions, there's no whole number oxidation state that would balance the charges with oxygen (which has a -2 oxidation state). Nevertheless, there is a hypothetical situation where we can calculate an average oxidation state for Fe in "Fe2O4".
Each oxygen has an oxidation number of -2, for a total of -8 for four oxygens. In order for the formula unit to be electrically neutral, the two irons must have a total oxidation number of +8 to balance this. Therefore, the average oxidation number for iron would be +8/2 = +4. However, keep in mind that this compound, Fe2O4, does not exist with iron only having a single oxidation state.
For our purposes, considering the information provided, we could match the hypothetical compound Fe2O4 with:
e. +4 (average oxidation number)
2. The oxidation number of Iron (Fe) as a free element is ___________.
The oxidation number of any element in its elemental form is always:
g. 0
3. The oxidation number of Fe in the compound FeCl3 is _______.
In FeCl3, each chlorine (Cl) has an oxidation number of -1. There are three chlorines, which give a total oxidation number of -3. For the molecule to be neutral, the Fe must have an oxidation number that balances this out. Therefore, the oxidation number of Fe in FeCl3 is:
a. +3
So the filled out answers would be:
1. e. +4 (hypothetically)
2. g. 0
3. a. +3