Questions tagged [color]
Questions where color (wavelengths associated with the visible region of the electromagnetic spectrum of about 400-800nm), or a color change is discussed.
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Is there water coloring that will maintain color at 80°C?
I'm building a keg cleaner for my employer. The cleaner has a caustic tank that uses PBW, and a sanitizer tank. The current build is plagued with caustic contamination, so I would like to see ...
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What is the source of the intense blue colour of ultramarine pigment?
The pigment ultramarine was once a rare, expensive and highly prized pigment for artists because of its intense, long lasting blue colour. It was one of the most expensive pigments used in renaissance ...
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Is there a cheaper alternative to Liquid Color Standards?
I'm trying to create a sensor that measures the fluid color within a PVC tube that exits from a patient's surgical wound.
I have a handheld spectrophotometer and a TCS3200 sensor, and I'm trying to ...
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Azo dyes with different colours than Yellow, Orange and Red [closed]
Why are there just Azo dyes with colours of Yellow Orange and Red. Do the molecules become to be unstable with a greater pi-electron System? Every dye or indicator with other colours are'nt Azo dyes.
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Are there any yellow ferrous (ideally stainless) alloys? Perhaps after heating?
I recently learned about purple gold, which is roughly 80%-20% Au - Al by weight. (It's beautiful.) I also know that Titanium will turn bright purple if heated sufficiently (probably an oxide layer). ...
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Extended resonance and colour [duplicate]
I was pretty sure that this would've been asked before but I couldn't find anything here. I've noticed that system with multiple benzene rings and pi donating/accepting groups tend to be quite ...
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Finding the pH level of a liquid process
A photo of 15ml of distilled water accompanied with 3 drops of both universal indicator and bromothymol blue were mixed together and taken (white background was put into the back of the beake). The ...
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Are there pigments that will only show their colour after applying water? [closed]
I am looking for pigments that at first are not showing their colour (and appear colourless), but after adding water or another 'component' like oil/alcohol etc. will show their colour.
My excuses for ...
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The colour of sunset yellow powder (red, orange, and yellow)
I asked about the colour of sunset yellow in water in the previous post (Changes of colour of sunset yellow in water).
And here, I would like to raise another question based on sunset yellow.
Sunset ...
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Changes of colour of sunset yellow in water
I am conducting an experiment on “sunset yellow (FCF)”.
Based on my observations, the substance, when in powder form, is bright red in colour (observed with naked eyes). When I dissolve the powder in ...
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Products formed on reaction of aqueous solution of iron(III) nitrate nonahydrate
Crystalline iron(III) nitrate nonahydrate, Fe(NO3)3.9H2O, has a very pale violet color. When added to water, the crystals dissolve to form a brown solution. Treatment of this brown solution with ...
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Colour of coordination compounds due to d-d transition
Hexaaquanickel(II) is green but tetracyanidonickelate(II) is colourless.
On internet I found two explanations.
One used valence bond theory that claimed there is no excitation of electron in ...
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Why Green Solution After Putting Bismuth Antimony in Nitrogen Acid
I am in a physics lab studying dislocation, and we submerged a bismuth antimony sample in nitrogen acid (about 50% concentration, if I remembered it right) as the first step to etch it. There were ...
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Silica gel reheating (orange)
I am a non-chemist looking for some advice! I am an archaeologist and am currently using moisture-indicating silica gel (orange) to dry out some metal finds from our excavations. I have reheated ...
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Color of coordination compounds
My book(Page $259$ section $9.5.5$) says that the color mainly comes from absorption of light in the coordination compound:
The color is complementary of the wavelength it absorbs , the wavelength ...
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