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What is a limiting reactant in the reaction between iron and sulfur?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

In a chemical reaction between iron and sulfur, the limiting reactant is not a fixed substance; rather, it is the specific reactant that is completely consumed first, thereby restricting the total amount of product that can be formed.1

The balanced chemical equation for this synthesis is:
$F e (s) + S (s) \to F e S (s)$

Because one atom of iron reacts with one atom of sulfur to produce one unit of iron sulfide, the identity of the limiting reactant depends entirely on the initial quantities provided. For example, if you begin with 5.585 grams of iron and 32.066 grams of sulfur, the iron will be consumed first, making it the limiting reactant, while a significant portion of the sulfur will remain unreacted. Conversely, if sulfur is provided in an amount insufficient to react with all the available iron, the sulfur becomes the limiting reactant.12