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Q & A: Dehydrated sponge water/alcohol question

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Most recent answer: 06/11/2009
I work in electronics repair and for our soldering irons we have a bunch of spare, "dehydrated" sponges. Usually I add a little water and they expand to about 10 times the orgiginal size. When I squirted Alcohol on them today they do NOT expand even a tiny bit. Why is that??? My thought is that they are both liquids and even thought the Alcohol will evaporate faster it should expand the sponge. I even completely saturated the sponge and still no expansion. Thank You for your time.
- Shawn McGlinchy (age 40)
Knoxville, TN, USA
Gee, that's a new one on me.  First of all the sponges on my soldering irons only swell up about a factor of two. I decided to make a test.  I don't have any full strength alcohol in the house so I used a 40% mixture (80 proof ) I keep around for snake bites.  The sponge soaked it up and seemed to like it as well as I do.  
I have a suggestion.  Try diluting your alcohol with water by various factors and see how the effect depends on the water/alcohol ratio.    Let us know your result.


(published on 06/11/2009)

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