Hydrophilic Powders (Jake Dickerman)

Author

Jake Dickerman

Principle(s) Illustrated

• Certain polymers in daily life are able to absorb massive quantities of water, based upon the chemical structure of the polymers. The powder within a disposable diaper is an example of chemical engineering in daily life.

• The powder in a diaper is Sodium Polyacrylate which will instantly polymerize and crosslink when combined with water

• This discrepant event could lead to an engineering problem where students would try to create their own super-absorbent powders or perhaps an engineering problem where students could try to create a non-polar super-absorbent powder to be used in oil clean-ups

Standards

• SEP: Constructing Explanations and Designing Solutions

• CCC: Structure and Function

• ETS1.c: Optimizing a Design Solution

Questioning Script

Prior knowledge & experience:

Water mixes with some things and doesn't mix with others. If you have students who have already learned some basic chemistry, they might be able to discuss polar vs. non-polar molecules.

Root question:

I have just poured water into this cup, will it pour back out? What sort of structures would help to capture large amounts of liquid?

Additional question: Is this change chemical or physical?

Target response:

Sponges, and paper towels might capture liquids.

Common Misconceptions:

Powders can't be used to clean up liquids

Photographs and Movies

Put all movies in your own Youtube account. Make sure that the account is set for public viewing. Insert the Youtube videos here.

References

References (give the title of the page and insert a link. Don't just paste a URL)