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Post by Mr. Kruse on Oct 30, 2008 20:22:51 GMT -6
www.youtube.com/watch?v=4_TQCiOQkioThis link has a science teacher doing a demo that puts hot and cold water against each other and also salt and fresh water against each other. He claims that density has something to do with the results, but does not explain how. You have several things to discuss in this thread. 1) How can you explain any of the four situations using density? 2) why is one type of water less dense than another? 3) what questions do you have about what this teacher has done? While watching the video, pause it and see if you can predict what will happen.
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Post by daniellemwakefield on Oct 31, 2008 9:29:55 GMT -6
2. in pure water dont they take some of the chemicals out so that means it shuldn't have agreater mass
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patricia schopp
Full Member
I have this pointy thing and i'm not afraid to use it
Posts: 106
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Post by patricia schopp on Oct 31, 2008 9:33:34 GMT -6
i did an experiment eactly like this in 3rd grade for a science fair. what happens is that the cold water is more dense than the hot water, so when he flipped it the second time it didn't mix unlike the first because the hot water rose and the cold water sunk. same with the salt water and tap water salt water is more dense than normal tap water, so when the salt water is on top they mix together, and when the tap water is on top it stays the same.
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Post by David Frost on Oct 31, 2008 9:39:38 GMT -6
that guy reminds me of u mr. kruse. by the way salt water has salt in it making mass greater and cold water molucles are closer together
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Post by austinburton55 on Oct 31, 2008 9:39:53 GMT -6
salt water has more density,which makes the tap water stay in the tube
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Post by Jeremy Riffenberg on Oct 31, 2008 10:06:38 GMT -6
.......? Ok....... But yeah, I pretty much agree with everybody and the whole "salthingyer" idea.
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patricia schopp
Full Member
I have this pointy thing and i'm not afraid to use it
Posts: 106
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Post by patricia schopp on Oct 31, 2008 10:08:10 GMT -6
.......? Ok....... But yeah, I pretty much agree with everybody and the whole "salthingyer" idea. what "salthingyer" |
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Post by Meranda Oban on Oct 31, 2008 10:13:38 GMT -6
 2.) I think that it has something to do with chemicals too. Because pure water has had chemicals taken out of it and salt water has not.
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Post by Jeremy Riffenberg on Oct 31, 2008 10:15:50 GMT -6
.......? Ok....... But yeah, I pretty much agree with everybody and the whole "salthingyer" idea. what "salthingyer" Salt* |
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Post by DerekHerron on Oct 31, 2008 10:19:41 GMT -6
I agree with some of the people to. I agree with burton when saying salthingyer has more density will something like tap water has pretty much less density in it.
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Post by Jeremy Riffenberg on Oct 31, 2008 10:22:33 GMT -6
Derek, "salthingyer" was my mistake. I was thinking and typing at the same time. Not a real word. >.<
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Post by Amy Hanson on Oct 31, 2008 10:29:53 GMT -6
i think that salt makes something more dense
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Post by brandonlong on Oct 31, 2008 11:00:38 GMT -6
i think that salt has more density 2
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Post by Mr. Kruse on Oct 31, 2008 11:04:48 GMT -6
what evidence is there that salt is more dense than water?
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Post by Victor Mar on Oct 31, 2008 11:09:48 GMT -6
what evidence is there that salt is more dense than water? mabe the salt in the water might bring the object up for air  |
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2.) I think that it has something to do with chemicals too. Because pure water has had chemicals taken out of it and salt water has not.