Imagine you have a mixture of iron filings, common salt, and ammonium chloride. Suggest a sequence of separation techniques you would use to separate each component from this mixture. Justify your choices.

Magnetic Separation: First, use a magnet to separate the iron filings, as iron is magnetic and the other components are not. 

Sublimation: Next, heat the remaining mixture (salt and ammonium chloride). Ammonium chloride sublimes (changes directly from solid to gas) upon heating, leaving behind the common salt. The ammonium chloride can be collected by condensation. 

Dissolution and Evaporation: Finally, dissolve the remaining common salt in water. Filter if any insoluble impurities are present. Then, evaporate the water to obtain pure common salt.