Lab 2.2: Mixture Separation

 

Name(s)          ___________________________                               Class  _______

                        ___________________________

Purpose

Separating out the different components in a mixture can often prove quite challenging, yet separation and recovery are extremely important operations both for research and for industry. In this lab you have an opportunity to develop and then implement your own self-designed procedure in an attempt to separate out and recover the components of a given mixture. The mixture contains the following four substances: salt, sand, iron filings, and poppy seeds, all essentially in dry granular form.

Procedure

1.         Obtain from the instructor a sample of the mixture and examine it carefully. Place a small, representative portion of the mixture (no more than 20% of what you are given) in the corner of a plastic sandwich bag, twist it closed, cut it off just above the twist and tape this small plastic sack to the lab sheet in the space at the end.

2.         Using any materials you want, develop and implement a procedure that enables you to separate out the mixture and recover all four components, each in as pure and dry a state as possible. Helpful Hint: If water is part of your procedure, be careful not to use too much! Also, if you use a magnet, wrap it in plastic wrap or a baggie.

3.         As each component is separated off, place it in a small plastic sack (as described above) and tape it to this lab sheet in the appropriate space at the end.

Analysis & Interpretation

1.         On a separate sheet of paper, in short, concise, numbered steps, write out the procedure you followed. It should be written clearly and thoroughly enough so that anyone not familiar with the lab could reproduce your results simply by reading and following your procedure.

2.         In your estimation, how successful were you (on a scale of 1-10) in separating and recovering each of the four components?

Sand: ___ Salt: ___ Iron filings: ___ Poppy seeds: ___

Conclusions (answer on a separate sheet of paper)

  1. What made you decide to do your procedure steps in the order that you did them? Would any order have worked?
  2. If you were to do the lab over again, what specifically might you do differently?
  3. For each of the four components (salt, sand, iron filings and poppy seeds), describe a specific physical property that enabled you to separate it from the rest of the mixture.

Extensions (answer on a separate sheet of paper)

  1. What might you do to determine the purity of each of your recovered components?
  2. How might you separate out each of the following 2-part mixtures (explain as well what physical properties of each substance would make this possible):

a.       lead filings and iron filings?

b.      sand and gravel

c.       sand and Styrofoam (both very finely ground)

d.      salt and sugar?

e.       alcohol and water?

f.        nitrogen and oxygen?

SEPARATED AND RECOVERED COMPONENTS (tape here)

representative portion of mixture

salt

sand

iron filings

poppy seeds