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General Discussion & Feedback => Radio Show & Podcast Feedback => Topic started by: jolly on 03/03/2007 20:01:51

Title: Got a question...maybe next sub. for podcast?
Post by: jolly on 03/03/2007 20:01:51
deleted as inapproprate
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 04/03/2007 00:48:24
Clouds are white because they reflect sunlight. When flying above clouds during the day, they are always bright white. When we get dark clouds, they are so thick that they soak up most of the sunlight or reflect it upwards, and so things aren't as bright below. Storm clouds are the thickest clouds, and look the darkest from below, though they look bright white from above.

alternatively:

Clouds are white because they are made from cotton candy. Cotton candy is composed mostly of sugar and spice and everything nice. Once the sugar is spun out of control it flies up into the atmosphere that is filled with angels and reindeer and small ships on their way to Roswell.

Some Native American Indians are called white cloud, and they are actually red!
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 04/03/2007 00:54:17
jolly,

read this http://sci.odu.edu/sci/scire/05Edition/whitecloud.html
Title: Got a question...maybe next sub. for podcast?
Post by: neilep on 04/03/2007 18:35:38
LOL...me is convinced by the alternative answer that Mr Paul.fr has given.....the former part of the post sounds too incredible to believe that I doubt it would stand detailed scrutiny  [;D]...LOL..I mean ..reflecting sunlight ?..how silly is that ?.....additionally....(and this is true) clouds are white because they have been Tipp-Ex'd out (Wite-Out) due to errors in the sky.......and they have been made white before being painted blue....and this is fact !!
Title: Got a question...maybe next sub. for podcast?
Post by: Karen W. on 04/03/2007 19:07:10
LOL..hey what about my cotton candy theory , you mean that I have been lied too???? Well all these years and I have wanted to sit amounst my cotton candy clouds and sing silly songs and bounce across the sky from one cloud to the next seeing if I could find just the right place to stop and rest my weary head!!! LOL
Title: Got a question...maybe next sub. for podcast?
Post by: Zwitterion on 04/03/2007 19:20:58
feel like eating candy floss after reading this....yum yum

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi121.photobucket.com%2Falbums%2Fo212%2FRS_200%2Fistockphoto_1794721_candy_floss_kid.jpg&hash=2237a55f70d31b21f003743d8b51ddf9)
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 04/03/2007 19:25:50
LOL..he what about my cotton candy theory , you mean that I have been lied too???? Well all these years and I have wanted to sit amonst my cotton candy clouds and sing silly songs and bounce across the sky from one cloud to the next seeing ig I could find just the right place to stop and rest my weary head!!! LOL

But am i right, Karen?

we have multiple "theories" as to why clouds are white, which is correct?

#1 by me: Clouds are white because they reflect sunlight. When flying above clouds during the day, they are always bright white. When we get dark clouds, they are so thick that they soak up most of the sunlight or reflect it upwards, and so things aren't as bright below. Storm clouds are the thickest clouds, and look the darkest from below, though they look bright white from above.

#2: again be me: Clouds are white because they are made from cotton candy. Cotton candy is composed mostly of sugar and spice and everything nice. Once the sugar is spun out of control it flies up into the atmosphere that is filled with angels and reindeer and small ships on their way to Roswell.

#3 by Neil: clouds are white because they have been Tipp-Ex'd out (Wite-Out) due to errors in the sky.......and they have been made white before being painted blue....and this is fact !!

and

#4 by jolly: because they all have salt


would anyone care to start a poll, that way we could get you a definitive answer?
Title: Got a question...maybe next sub. for podcast?
Post by: Karen W. on 04/03/2007 19:53:02
 WAHHHHHHHH< I am so confused, Not hard to do!! WHO THE H*** TOOK ME off MY ship!!!! lol I WAS HOPING to meet some sweet loving aliens who would wuv me forever!! LOL
Title: Got a question...maybe next sub. for podcast?
Post by: Karen W. on 04/03/2007 19:58:14
BTW paul, I think you might be right, but then again, I may be mistaken after the last brain probe on the way to roswell, I have no real sense of right or wrong anymore.. LOL You might ask Neil he was on the other ship! going a different direction thus the other answer!! LOL
Title: Got a question...maybe next sub. for podcast?
Post by: neilep on 04/03/2007 21:24:01
Does this mean that grey clouds are white clouds poo ?
Title: Got a question...maybe next sub. for podcast?
Post by: Karen W. on 04/03/2007 21:54:55
LOL who knows mine are rainbow colored so there!
Title: Got a question...maybe next sub. for podcast?
Post by: jolly on 04/03/2007 22:26:27
I think its cloud faries which paint clouds white while we sleep.
Title: Got a question...maybe next sub. for podcast?
Post by: neilep on 04/03/2007 22:44:29
Yes , yes...I believe it's the cloud fairies too !!....

I am so confused now...each and every explanation rings true !!
Title: Got a question...maybe next sub. for podcast?
Post by: Karen W. on 05/03/2007 01:01:08
Yes indeedy Sir, At least we all have one final veiw.. awesome clouds!! LOL
Title: Got a question...maybe next sub. for podcast?
Post by: rosy on 05/03/2007 09:21:32
Jolly, as I explained before salt DOES NOT evaporate with water. It just doesn't happen. I'm not going to attempt to explain why, because such subtleties as that would clearly be too much for you (and I doubt you'd read it).
I believe I explained this in one of my posts to the why-does-ice-float thread. Infact, here is the section of my post:
Quote
On the point of water rising up from the sea to form clouds... the white colour of clouds is due to the fact that the light shining through them gets refracted (undergoes a change of direction due to passing from one material into another, water into air and vice-versa) many times and so whereas when there are no clouds the sky appears blue and the sun yellow the colours are all mixed up to make white (see weblink below):
http://www.sciencemadesimple.com/sky_blue.html
Darker clouds are due to a substantial part of the light being stopped on its way through (and reflected back out into space/converted into infrared, which we can't see). The salt stays in the sea. Period. For a whole range of reasons I won't go into here because this post is already too long.
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 05/03/2007 13:30:52
Jolly

As Rosy, and many others including mtself, have previously stated salt does not evaporate with water. I will try one last time to to make you understand.

Clouds are formed when air near the ground is mixed with water vapour (from puddles, streams, lakes, oceans or any other source of water). To make clouds this moist air must be carried upwards. This is because air cools as it rises and when the water vapour in the air is cooled enough some of it will change back into drops or even into ice crystals. These drops or ice crystals make the clouds we see. Clouds come and go depending on the temperature of the air and how much water vapour is mixed with it. If the air in a cloud warms, the cloud may disappear when the drops evaporate again.

Ice, does not contain salt either. When ice is formed, say at sea, any salt contained in the water is pushed out. This is why you are able to drink ice water, after you have melted it.
The reason water expands when it is cold enough for it to turn to ice, is because water molecules are shaped like a boomerang, and have an angle of 104.5 degrees. When the water cools dow n the little "boomerangs" spread out and take up more room.

If you can prove that clouds, etc. contain salt i will respond, otherwise i think this topic is finished.
Title: Got a question...maybe next sub. for podcast?
Post by: another_someone on 05/03/2007 13:36:50
why is snow, steam and clouds all white? I think its because they all have salt in them can you give me an answer? dark clouds dont count as their dark coz light cant get through them.

OK, how about, why is the sea not white - it has a lot of salt in it?

There are also a lot of other things that are white that do not have salt in them (or are you suggesting that everything that is white must contain some salt?).
Title: Got a question...maybe next sub. for podcast?
Post by: jolly on 05/03/2007 19:30:36
deleted as inapproprate
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 05/03/2007 19:42:57
ok, i let myself down and am replying....

Now jolly, if your question had been:

"i think clouds have salt in them because i cought some rain, tested it and found salt in it"

That would have been an excellent question, and easy to answer. As we all know clouds do not contain salt, but rain water can.

It is possible that on the way down as rain water, salt is collected in the rain. This could happen if you were near the coast, and bad weather causing large waves  which were blowing salt water into the air.
Title: Got a question...maybe next sub. for podcast?
Post by: Bored chemist on 05/03/2007 20:05:20
OK time for the contraversial post. Salt isn't particularly white!

Big pure crystals of salt get used in infra red spectroscopy because they are transparent to IR radiation (across quite a large range). If you look at one of these crystals it looks prettty much like a piece of glass. or, indeed, like a piece of (bubble free) ice.

Also, while that's not why I did the experiment, I have analysed rain water- it had less stuff dissolved in it than the tap water here and the tap water certainly doesn't taste salty. OK I only did a conductivity measurement on it, rather than a full analysis but I still say there's very little salt in rainwater.
I was wondering if it was worth trapping rainwater to use rather than distilling tap water (just in case anyone wondered why I wa tooking at rain).
Title: Got a question...maybe next sub. for podcast?
Post by: paul.fr on 05/03/2007 20:12:31
OK time for the contraversial post. Salt isn't particularly white!

Big pure crystals of salt get used in infra red spectroscopy because they are transparent to IR radiation (across quite a large range). If you look at one of these crystals it looks prettty much like a piece of glass. or, indeed, like a piece of (bubble free) ice.

interestingly, or not, Anastasia made a microscope slide of salt and as you state mr chemist, it does indeed look like a piece of glass
Title: Got a question...maybe next sub. for podcast?
Post by: another_someone on 05/03/2007 20:59:12
well water shines if you look at it from an angle. but the light is absorbed as it hits and heats up the water(evaporation). so maybe it shines because the salt in it bounces the light off it. and from an angle it does look white. Right if you evaporate salt water and catch the steam and let it condense back into water and then test it for salt. does it still have some salt in it. If it does then I could be right. Better still why not catch rain water and see if there is any salt there. maybe just a small amount. I think there will be, would someone please go and test some rain water, for me! I dont have the equipment.

So, how about another aspect of this - when it snows, one way of getting the snow to melt is to add salt to it - clearly indicating that there is a difference between salted snow and unsalted snow, and the stuff you get comming from frozen rainwater is the unsalted variety (and, interestingly, it is the unsalted variety, that while it is more frozen, is also the whiter).

Not that I think any of this is is going to make the slightest difference to your response, since you clearly have an idea in your head that no amount of contrary fact will shift (or so you would have us believe - I have yet to be convinced that even you believe half of what you are saying, and are not just saying it to be provocative - I actually think you are probably brighter than the rather stupid act you are trying to put on).

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