Brown-black

Cleaning flasks. Flasks, specially distilling flask are really dirty, with a brown black semisolid tar. It s easy to clean them. Make a 25 % or stronger NaOH solution (from drugstore, of course), put it in the flask and heat, till boiling if necessary, all tar go out easy. Use gloves, please. 

TrisaZO and Polyazo Dyes. These are mostly direct dyes, the hues ate predominandy brown, black, or dark blue or green. Some are leather dyes. Benzidine, which used to be an important bisdiazo component, has been replaced by 4,4 -diaminobenzanilide [785-30-8] ... 

Naturally occurring cadmium compounds are limited to the rare minerals, greenockite [1317-58 ] CdS, and otavite (1), an oxycarbonate, but neither is an economically important source of cadmium metal or its compounds. Instead, cadmium compounds are more usually derived from metallic cadmium [7440-43-9] which is produced as a by-product of lead—2inc smelting or electrolysis (see Cadmiumand cadmium alloys). Typically, this cadmium metal is burnt as a vapor, to produce the brown-black cadmium oxide [1306-19-0], CdO, which then acts as a convenient starting material for most of the economically important compounds. 

Mascara pigmentation is usually black or brown—black. Mascaras during and after appHcation are extremely close to the cornea, and any potential irritant must be rigidly excluded. The use of lash-elongating synthetics, such as rayon, nylon, and the like, has not resulted in significant problems. 

Chemical Properties. When heated in a dry CO2 atmosphere, sodium cyanide fuses without much decomposition. A brown-black color... 

PPS resins are chiefly used for injection mol ding. The melt flow of the glass-fiUed resins is very stiff, and high injection pressures are required. Mold surface wear is heavier than for most other engineering plastics. Mol ding melt temperatures are near 330°C for optimum surface gloss and impact strength, mold temperatures of 130°C should be used. The resins are brown to brown-black. 

Observable Characteristics - Physical State (as normally shipped) Solid Color. Brown-black Odor. None. 

PTFE IS insoluble in all known solvents and resists attack by most chemicals, although its surtace is readily degraded by alkah metal-anunonia solutions. Such solvated electron media etch PTFE to produce a brown-black layer quite unlike the onginal white, low-friction, nonstick surface... 

Thallium is notably different. TI2O forms as black platelets when TI2CO3 is heated in N2 at 700° (mp 596°, d 10.36 gcm ) it is hygroscopic and gives TlOH with water. Tl" 03 is brown-black (mp 716°, d 10.04gcm ) and can be made by oxidation of aqueous TINO3 with CI2 or Br2 followed by precipitation... 

Colour Yellow Black Brown-black Brown Grey Black Grey Grey Grey... 

Anil Black Brown Black Purple Green Yellow White Yellow Yellow t... 

Braun-saLz, n, any of certain brown dyes. -schliff, m. (Paper) steamed mechanical wood pulp, brown wood pulp, braunschwarz, a, brown-black, very dark brown. 

Note Reducing sugars do not react [1]. In the course of a few days the chromatogram zones gradually acquire brown-black discoloration, presumably as a result of the production of elementary selenium [1]. 

Te (tellurium, brown black, amorphous), Te02 (tellurous anhydride, white), Te02 hydr. (tellurous acid, H2Te03 or Te02-H20, white, amorphous), TeOs hydr. (orthotelluric acid, H6Te06 or Te03 3H20, colorless, cubic or monoclinic). 

Color Multiple colors of various hues of light brown, dark brown, black, red, blue, or gray. 

Most of the desert pavement stones are covered with a brown-black and shiny crust. When the stones are composed of limestone, the dark crust contrasts strongly with the much lighter inside color exposed on fracture surfaces. The crust forms on various stones, both sedimentary and igneous and is also known under the name of desert varnish , or desert patina . The varnish is less common on non-resistant rocks such as a soft limestone. These, apparently, disintegrate before the crust has time to develop. 

The reaction mixture turns from a yellow-orange color to a dark brown/black during the warming process, at ca. -35° to -25°C. 

Microcrystalline wax is found worldwide as a constituent of crude oil. It is removed by solvent extraction and distillation. The colour varies, depending on grade, from white to brown black. It has many uses, including waterproofing paper and textiles, and as a sealant. This wax consists of a mixture of long chain (C41 C57) unsaturated hydrocarbons with an average molecular weight of 500 800. 

The colors purple, brown, black, and gray have not been assigned a safety connotation. Specific color codes are also employed in the identification of alarms panel indicators, piping, compressed gas cylinders, electrical wiring, fire sprinkler temperature ratings, etc. Although these sometimes do not correspond with similar meanings. 

Melanin from natural sources falls into two general classes. The first component is pheomelanin (I), which has a yellow-to-reddish brown colour, and is found in red feathers and red hair. The other component is eumelanin (which has two principal components, II and III). Eumelanin is a dark brown-black compound, and is found in skin, hair, eyes, and some internal membranes, and in the feathers of birds and scales of fish. Melanin is particularly conspicuous in the black dermal melanocytes (pigment cells) of dark-skinned peoples and in dark hair and is conspicuous in the freckles, and moles of people with lighter skins. 

Yellow Orange Red Violet Blue Green Brown Black ... 

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