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Post by ironhold on Dec 16, 2012 22:05:11 GMT
All experiments posted in this section should be done with adult supervision in a controlled environment and with reasonable safety precautions.
Additional recommendations: Perform this experiment in an area that is water-proof; the experiment involves the use of water, which can potentially lead to spills. ** Capillary action is the ability of a liquid to pull itself up into narrow vessels, even in spite of gravity. Sounds awesome, right? How'd you like to see it in action? Take a small container, such as an empty yogurt cup, and fill it with water. Obtain a paper towel. The brown, grainy towels that are frequently used in schools, government buildings, and other such institutions work best for this. Dip one corner - and one corner only - of the paper towel into the container of water. Ensure that the rest of the paper towel does not make contact. Allow the corner of the towel to remain in contact with the water. Observe what's happening. If you'll note, the water is slowly being pulled up into the paper towel, with the dry parts visibly (if not quickly) becoming wet and the water level in the container slowly going down. That, ladies and gentlemen, is capillary action at work.
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Post by c64 on Dec 17, 2012 13:26:08 GMT
There is an even more obvious experiment you can do. Just get one of those useless thin straws with the 1mm gauge and put it into a glass of water. You can see that the water level inside the straw is a millimeter or two higher.
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Post by GTCGreg on Dec 17, 2012 14:53:10 GMT
I seem to remember my 7th grade science teacher showing us that. (thin straw)
The fact that I remember her doing that over 50 years ago must mean it made an impression on me.
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Post by Cybermortis on Dec 17, 2012 15:05:40 GMT
A related test is to place a drop of ink about half an inch below the bottom edge of a strip of paper. Allow it to dry and then suspend it so only the lowest 1/4tr of an inch is in water. Leave it for a few hours and see how the ink has diffused up the paper...but in differently coloured bands.
This is known as paper chromatography, and is a scientific technique used in labs to separate pigments.
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Post by privatepaddy on Dec 18, 2012 12:27:13 GMT
If you use paper first then cut a shallow groove around a stick of chalk at 12.5 mm from the bottom and fill the grove with the same washable ink place the chalk stick in 6mm of water and allow the water to wick you will note something interesting between the two experiments. a hint. polarity.
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Post by c64 on Dec 18, 2012 18:26:43 GMT
A related test is to place a drop of ink about half an inch below the bottom edge of a strip of paper. Allow it to dry and then suspend it so only the lowest 1/4tr of an inch is in water. Leave it for a few hours and see how the ink has diffused up the paper...but in differently coloured bands. This is known as paper chromatography, and is a scientific technique used in labs to separate pigments. Correct, but that's not to demonstrate capillary action - at least as not more than demonstrating the basics of a lever by firing an MG at a car. |
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Post by rmc on Dec 20, 2012 1:50:22 GMT
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Post by chriso on Dec 29, 2012 8:52:46 GMT
Got something even better. Plants use capillary action to bring water into themselves, and using this knowlege you can make a white flower multicolored.
Take a white flower, and have your parent split its stem down the center to about half way up the stock. Take two containers, fill them with water, and put a different food coloring in both. Now, place the containers somewhere they will not be disturbed for two weeks or so, and put one of the two ends of the stocks in each container. Wait...
In two weeks, your white flower will of wicked up the water, and with it the food coloring, giving you a flower that is partially one color, partially another, and nowhere white.
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Post by c64 on Dec 29, 2012 17:20:24 GMT
Got something even better. Plants use capillary action to bring water into themselves, and using this knowlege you can make a white flower multicolored. Take a white flower, and have your parent split its stem down the center to about half way up the stock. Take two containers, fill them with water, and put a different food coloring in both. Now, place the containers somewhere they will not be disturbed for two weeks or so, and put one of the two ends of the stocks in each container. Wait... In two weeks, your white flower will of wicked up the water, and with it the food coloring, giving you a flower that is partially one color, partially another, and nowhere white. Or just put it into the waste from your photo lab, then you get a rainbow coloured flower until it rolls up its leaves (or drops them) five minutes later ;D |
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Post by c64 on Dec 29, 2012 17:22:51 GMT
[…] have your parent split its stem […] Bad idea, why should I want to drive 50 miles to have someone who has serious Arthritis in her fingers or someone who can't really feel his fingers use a knife for me? I could ask my mum's mother but she probably either don't know who I am or what a knife is… {You DID read the forums description...right? - CM} |
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Post by blazerrose on Jan 4, 2013 3:47:07 GMT
My grandmother showed me how plants use capillary action by using a celery stalk and red food coloring. Pretty neat demonstration. She cut the bottom of the stalk to create a clean end, then put it in a glass with water and red food coloring. It was fun to see the pink stripes up the celery stalk.
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