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Zarkov
Oh I know colour is not real, it is all in the mind, nevertheless there is a lot of hype re colour.

In visible light certain gases appear to be colourless, eg N2, CO2 etc

others appear to be coloured eg Cl2, Br2 etc

It appears other gases, even though their liquid is highly coloured, are claimed to be colourless.

Water for instance (is not a gas, but steam is).... is pale blue.... and yet steam is 'colourless' ?

Other gases still are supposedly coloured by the scattering of light ?.... and example of this is oxygen even though the solid is blue-black, and the liquid is sky blue. Ozone is another enigma.

In all cases except some ??claims, if the solid is coloured, and the liquid is coloured the gas is also coloured.

Can a gas have a colour ? or is the colour that is seen due to some interference of visible light ?

Can a gas cause visible light interference ?


Why is the sky BLUE ? is a good question.
Sandra doliak
QUOTE (Zarkov+Jul 21 2008, 07:14 AM)
Oh I know colour is not real, it is all in the mind, nevertheless there is a lot of hype re colour.

In visible light certain gases appear to be colourless, eg N2, CO2 etc

others appear to be coloured eg Cl2, Br2 etc

It appears other gases, even though their liquid is highly coloured, are claimed to be colourless.

Water for instance (is not a gas, but steam is).... is pale blue.... and yet steam is 'colourless' ?

Other gases still are supposedly coloured by the scattering of light ?.... and example of this is oxygen even though the solid is blue-black, and the liquid is sky blue. Ozone is another enigma.

In all cases except some ??claims, if the solid is coloured, and the liquid is coloured the gas is also coloured.

Can a gas have a colour ? or is the colour that is seen due to some interference of visible light ?

Can a gas cause visible light interference ?


Why is the sky BLUE ? is a good question.

Notice when we look at the ocean, it is "blue", but when it is poured out of a tap, it is "color less'. When being poured out of a tap, there isn't much water to absorb all of the color spectrum except blue. perhaps the same applies with Cl2 and Br2. Their liquid form is much denser.

QUOTE
In all cases except some ??claims, if the solid is coloured, and the liquid is coloured the gas is also coloured.
If this statement was true, then if there are clear solids and liquids, then there will be clear gases. Alas! gas isn't as dense as its sisters, the solid and the liquid. Solving the ridiculuos result of "colorless gases"

And how dense is Cl2 and Br2 compared to the other "colorless" ones? And besides, if enough was gathered of a supposed colorless gas, than it would have a color.

A famouse example and experiment of this would be the classical "mirror". In which 3 mirrors are placed in a triangular formation, and where 2 points meet, is one allowed to see, when a person glasses into this, he will see approximately 50 reflected mirrors reflecting themselves, this number obviously increases the smaller the gap is where a person glances through. The result is surpassing. The more of something "apparently colorless" is gathered, the greater chance of us seeing a color.

Another example is with tap water, it comes out colorless, but when large amounts is gathered, such as the ocean, the color blue suddenly is there.

Sandra
N O M
Zerkoff, you never fail to amaze with your stupidity and ignorance.

Colour is merely due to either absorbed or reflected light. The constituents of our atmosphere absorb very little visible light.

The sky is blue because of diffracted light from the sun. The higher wavelengths diffract more.

And water is not blue.
Zarkov
NOM
QUOTE
you never fail to amaze with your stupidity and ignorance.


LOL

and ice is pink !!!

LOL

SD is far more on the money that the clowns of this forum.
excaza
Water is not blue. Water has no color.
midwestern
A real brilliant discussion here. laugh.gif
prometheus
QUOTE (excaza+Jul 21 2008, 10:48 AM)
Water is not blue. Water has no color.

Water is actually slightly blue. Thats what it said on QI anyway... biggrin.gif
prometheus
From the Wikipedia article

QUOTE (Wikipedia+)
Pure water has a light blue color which becomes a deeper blue as the thickness of the observed sample increases. The blue color is caused by selective absorption and scattering of the light spectrum. Impurities dissolved or suspended in water may give water different colored appearances.


I think for the first time ever, Zarkov is right! ohmy.gif

Edit: To answer the original question, gasses certain can be different colours - for example, gaseous bromine and nitrogen dioxide are brown
User posted image: http://www.chem.purdue.edu/gchelp/liquids/bromine.gif
User posted image: User posted image

chlorine is green.

User posted image: User posted image

The sky is blue because of Rayleigh scattering
midwestern
Yes, he is and now you know why I made the comment. tongue.gif biggrin.gif
N O M
QUOTE (prometheus+Jul 22 2008, 07:25 AM)
I think for the first time ever, Zarkov is right! ohmy.gif

I regretfully admit that in this one instance this may actually be the case.

That is a problem with idiots like zerkoff. We get so used to everything he posts being complete utter drivel, that when he sneaks an actual fact into a post it's just automatic to assume it is wrong.
barakn
QUOTE (Zarkov+Jul 21 2008, 03:55 AM)
LOL

and ice is pink !!!

LOL
midwestern
Good going Zark or luck? rolleyes.gif unsure.gif huh.gif
Zarkov
QUOTE
The sky is blue because of Rayleigh scattering


oh lookie here

we have an exception.... LOL

as if
excaza
QUOTE (prometheus+Jul 21 2008, 02:25 PM)
From the Wikipedia article

QUOTE (Wikipedia+)
Pure water has a light blue color which becomes a deeper blue as the thickness of the observed sample increases. The blue color is caused by selective absorption and scattering of the light spectrum. Impurities dissolved or suspended in water may give water different colored appearances.


I think for the first time ever, Zarkov is right! ohmy.gif

Edit: To answer the original question, gasses certain can be different colours - for example, gaseous bromine and nitrogen dioxide are brown
User posted image: <a target='_blank' href='http://www.chem.purdue.edu/gchelp/liquids/bromine.gif'>http://www.chem.purdue.edu/gchelp/liquids/bromine.gif</a>
User posted image: <a target='_blank' href='http://www.dkimages.com/discover/previews/833/60020413.JPG'>User posted image</a>

chlorine is green.

User posted image: <a target='_blank' href='http://www.webelements.com/_media/elements/element_pictures/Cl.jpg'>User posted image</a>

The sky is blue because of Rayleigh scattering

huh, guess I was wrong.

Wasn't there a book about racism called "the color of water?" Kid asks his mom what color he is and she says "water," implying that it doesn't matter. Guess she's actually telling her kid he's blue tongue.gif
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