Iron and sulfur can be separated by using carbon disulfide because iron sulfide is insoluble in carbon disulfide, while iron is soluble. The process of separation involves the following steps:

1. Grinding: The mixture of iron and sulfur is first ground into a fine powder to increase the surface area and facilitate the separation process.

2. Addition of Carbon Disulfide: Carbon disulfide is added to the powdered mixture. Iron sulfide being insoluble in carbon disulfide remains as a solid, while iron dissolves in carbon disulfide, forming iron(II) sulfide:

FeS(s) + CS2(l) → No reaction

Fe(s) + CS2(l) → Fe(CS2)2(l)

3. Filtration: The mixture is filtered to separate the solid iron sulfide from the solution containing iron(II) sulfide. The insoluble iron sulfide is collected as a residue on the filter paper, while the solution containing iron(II) sulfide is collected in a separate container.

4. Evaporation: The solution containing iron(II) sulfide is heated to evaporate the carbon disulfide. As the carbon disulfide evaporates, iron(II) sulfide is recovered as a solid residue.

5. Collection and Drying: The recovered iron and iron sulfide are collected, dried, and weighed to determine their respective amounts in the original mixture.

Here are the chemical equations for the reactions involved:

Dissolution of iron:

Fe(s) + CS2(l) → Fe(CS2)2(l)

Evaporation of carbon disulfide:

Fe(CS2)2(l) → FeS(s) + CS2(g)

By using carbon disulfide as a selective solvent, iron can be effectively separated from sulfur in the mixture.