Question: How do you separate iron related material and a non-magnetic material in a mixture?

Answer: Use magnets. This is because iron is a magnetic material and it can be attracted to the magnet while the non-magnetic material can't. So therefore, the iron can be separated fron the non-magnetic material.

Question: When a solid is dissolved in water you can separate the two by?

Answer: You can separate them by evaporating the water. Once all the water has evaporated, the solid would 'emerge'. We can also use filration.

Question: Separate solid that cannot dissolve in liquid.

Answer: There's serveral methods for this one. If the solid is magnetic, we can use a magnet to separate the solid from the liquid. If not, we could use a filter. Distillation is fine too. We can also evaporate the water, leaving the solid behind.

Question: Separate Liquid and Liquid.

Answer: We can use distillation and fractional distillation.

Question: Air and petroleum?

Answer: Use fractional distillation or distillation because both of them have different boiling points.