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Author: Subject: What is white, transparent, and translucent?
eVBoy
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[*] posted on 1-6-2016 at 12:56
What is white, transparent, and translucent?


I mean snow is white, ice is translucent to transparent, water is transparent. Why? How?
What about NaCl, NaOH, CaCO3, MgO, SiO2 and many white/transparent compounds?
Would they look like glass after melting and cooling? Can glass become white?
I think white is when transparent compound is sintered, and transparent when molten?
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careysub
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[*] posted on 1-6-2016 at 13:03


Any type of condensed matter that can be transparent will also be white and translucent.

It is a matter of particle size and scattering. Finally powdered materials (often even strongly colored ones) are white since the small particles scatter light of all wavelengths.

Translucence is just imperfect transparency (more or less, usually due to structural irregularities producing limited scattering).

[My initial answer to the post subject was: "An egg, a window and my shower curtain" given that it was not specified that it had to be the same thing.]
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j_sum1
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[*] posted on 1-6-2016 at 14:45


Particle size has a large effect on perceived colour.
Finely divided gold appears a dull brown. Silver appears black. And the streak of iron pyrite is black while the bulk material is a yellow-gold colour.
It is the same principle of scattering at work. Any sufficiently powdered transparent material will appear white.

Don't believe your eyes.




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halogen
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[*] posted on 2-6-2016 at 11:06


it's the same reason that sand flows through a sieve. the particles of light are smaller than the pores of the matter. some matter has smaller pores, like metal, which rejects the light but allows x-rays and so on. other materials have holes of intermediate size, and the light particles become trapped and can't get out: these we perceive as black, or various colors, like blue, green etc.



F. de Lalande and M. Prud'homme showed that a mixture of boric oxide and sodium chloride is decomposed in a stream of dry air or oxygen at a red heat with the evolution of chlorine.
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[*] posted on 2-6-2016 at 11:09


Take a mirror, for instance. It reflects a good picture of the world. Break it in half, still kind of does. But as the number of fractions you devide the mirror into increases, there will be a disaster, and you'll no longer see a good reflection.



F. de Lalande and M. Prud'homme showed that a mixture of boric oxide and sodium chloride is decomposed in a stream of dry air or oxygen at a red heat with the evolution of chlorine.
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PHILOU Zrealone
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[*] posted on 2-6-2016 at 14:29


Quote: Originally posted by j_sum1  
Particle size has a large effect on perceived colour.
Finely divided gold appears a dull brown.

At a certain particle size it (colloidal gold) is even purple and blue...it was/is part of pregancy test.

[Edited on 2-6-2016 by PHILOU Zrealone]




PH Z (PHILOU Zrealone)

"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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