Does anyone know how to answer this question:
Antimony is a solid element that is used in industry. The method used for theextraction of antimony depends on the grade of the ore.
3 (a) Antimony can be extracted by reacting scrap iron with low-grade ores that containantimony sulfide (Sb2S3).
3 (a) (i) Write an equation for the reaction of iron with antimony sulfide to form antimony andiron(II) sulfide.
I might be missing something really obvious but I don't get how you're supposed to know how many irons react with the sulfur.