Water Presentation

By Andy Cook

If you partially fill a cup with water and dump it upside down in water, why doesn't the air fall out?

If you take the same cup and raise it above the water level without taking it all the way out of the water, why doesn't the water fall out?

Why does ice float?

What would the world be like if the air was heavier than the water?

What would it be like if ice sank in water?

How would fish in a frozen lake react if the ice formed from the bottom up?

Atmospheric pressure

Place your straw in the capsule of water and place your finger over the top of the straw. Now take the straw out and the water will stay in just like in an upside down cup.

This is caused by the weight of the air.

Yes, air has weight!

The air can only enter the straw two ways. The first is if you remove your finger and let the air in the top.

The second way is if the air pressure is strong enough to break the surface of the droplet of water on the bottom of the straw and sneak it's way up.

Those are actually the only two natural ways for the water to be released from the straw. The last way would be to actually force the water out.

How?

Water Activity

Another cool thing about water is it's polarity!

Covalent bonds-The hydrogen and

oxygen atoms share the electrons

Oxygen hogs the electrons giving it a negative charge and leaving the hydrogen with a positive charge.

This gives us a situation like this:

(H) (H)

( O ) (H)---( O )

(H)---( O ) (H)

(H)

/

( O )

(H) (H)

This polarity in the water is actually what allowed the drop of water on the end of the straw to hang out so far without dropping off.

Water Activity

QUESTIONS?

Works Cited

http://www.madsci.org/posts/archives/2000-05/959607056.Ph.r.html

http://www.auburn.edu/projects/sustainability/newsletter/water.jpg

http://farm2.static.flickr.com/1357/855466139_2c7537e555.jpg

http://unrealitymag.com/wp-content/uploads/2009/06/atomic-water-full-size.jpg http://images.google.com/imgres?imgurl=http://farm2.static.flickr.com/1357/855466139_2c7537e555.jpg&imgrefurl=http://www.darkroastedblend.com/2007

/11/liquid-art-droplet-photography.html&usg=__a-ox_ak_6h1DYnRciY7lKhrzo8s=&h=375&w=500&sz=156&hl=en&start=2&sig2=56SrDPyFJ9KoWRCi38AvEw&itbs=1&tbnid=rgCwdmtbmBzsMM:&tbnh=98&tbnw=130&prev=/images%3Fq%3Dwater%2Bdroplet%2Bphotography%26hl%3Den%26gbv%3D2%26tbs%3Disch:1&ei=lgSGS6rWC5SctAOvtYD_CA

http://www.sustainabilityninja.com/wp-content/uploads/2009/03/water_bottles_bad.jpg

http://www.eyesontutorials.com/images/Effects/VladStudio/tut24_UnderwaterWallpaper/Underwater_1024x768.jpg