Design an experiment that would allow you to separate out a mixture of iron filings, sand and salt.

Sure, here's a step-by-step guide to separate a mixture of iron filings, sand, and salt:

1. Magnet Separation: The first step would be to use a magnet to attract the iron filings out of the mixture, leaving the sand and salt. Iron is magnetic while sand and salt are not. This process is known as magnetic separation.

2. Dissolution: Next, add water to the remaining mixture of sand and salt. Stir the mixture thoroughly. The salt will dissolve in the water, while the sand will not.

3. Filtration: Now, pour the mixture through a filter (like a coffee filter or a piece of cloth). The sand will be caught in the filter, while the saltwater will pass through. This process is known as filtration.

4. Evaporation: Finally, to separate the salt from the water, heat the saltwater gently until the water evaporates, leaving the salt behind. This process is known as evaporation.

By following these steps, you can successfully separate a mixture of iron filings, sand, and salt.