Final answer:
The limiting reactant is the reactant that is completely consumed first and limits the amount of product formed in a chemical reaction. To identify it, one must convert the mass of reactants to moles and compare their mole ratios based on the balanced chemical equation.
Step-by-step explanation:
To determine the limiting reactant in a reaction mixture, you need to know the balanced chemical equation and the initial amounts of each reactant.
In the reaction of zinc sulfide (ZnS) with oxygen (O₂), the chemical equation would guide us to find out which reactant is consumed first based on the stoichiometric coefficients which represent the mole ratio in which the reactants combine.
Using the balanced chemical equation, we can calculate how much of one reactant is needed to react completely with a given amount of another reactant. The reactant that is completely consumed first is the limiting reactant because it determines the maximum amount of product that can be formed.
Without the balanced equation for the reaction between ZnS and O₂, we can't directly determine which is the limiting reactant.
However, if we consider a hypothetical compound with two hydrogen atoms, one sulfur atom, and four oxygen atoms, we can perform a similar calculation. We would need to find the molar ratio of the reactants to the product and compare the amounts of reactants available to see which will run out first.
For the reaction that produces sodium chloride from sodium and diatomic chlorine, we convert the mass of each reactant to moles and use the balanced equation to compare the mole ratios. The reactant that has the smaller mole ratio (based on the stoichiometric coefficients) is the limiting reactant.
It is essential to convert mass to moles because reactions proceed based on the number of particles (moles) and not on the mass. This is why even a larger mass of one reactant doesn't necessarily mean it won't be the limiting reactant.