The compound [iron(II) nitride] has the formula:
Fe(NO3)2
Fe3N2
Fe₂N
FeN
The Correct Answer and Explanation is :
The correct formula for iron(II) nitride is Fe₃N₂.
Iron(II) nitride is a binary compound consisting of iron and nitrogen. In this compound, iron typically exhibits a +2 oxidation state, and nitrogen exhibits a -3 oxidation state. However, the stoichiometry and the chemical formula of iron nitride can be confusing because of the multiple oxidation states iron can adopt and the various ways nitrogen can combine with iron.
Here’s a breakdown of why Fe₃N₂ is the correct formula:
- Valency and Oxidation States: Iron (Fe) can exhibit multiple oxidation states, but in iron(II) nitride, it specifically adopts a +2 oxidation state. Nitrogen (N), typically in binary metal compounds, has a -3 oxidation state. To balance the total positive and negative charges in the compound so that the compound is electrically neutral, a correct ratio of iron to nitrogen atoms is needed.
- Formulating the Compound: With iron having a +2 charge (Fe²⁺) and nitrogen a -3 charge (N³⁻), the simplest way to balance these charges in a compound is to use a multiple that equals the lowest common multiple of the charges. Thus, for every two iron(II) ions (total +4 charge), there are two nitrogen ions (total -6 charge), which does not balance. Increasing the iron count to three (total +6 charge from Fe²⁺ x 3) and the nitrogen to two (total -6 charge from N³⁻ x 2) balances the charges, leading to the formula Fe₃N₂.
- Stability and Composition: Fe₃N₂ forms a stable compound under specific conditions, usually involving high temperatures and controlled environments, which further verifies the empirical formula derived from balancing the charges.
The error in the other formulas provided:
- Fe(NO₃)₂ suggests a compound of iron with nitrate, not nitride.
- Fe₂N and FeN do not correctly balance the charges based on the typical oxidation states of iron and nitrogen in this context.
I will now generate an image that visually represents the molecular structure of iron(II) nitride, Fe₃N₂.
Here is the visual representation of the molecular structure of iron(II) nitride, Fe₃N₂. The image illustrates the crystal lattice with iron atoms depicted as larger spheres and nitrogen atoms as smaller spheres, highlighting the stoichiometry and the balanced charges between the elements. This structure showcases how the atoms are arranged to form the compound.
