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A flame test involves introducing a sample of the element or compound to a hot, non-luminous flame and observing the color of the flame that results. [4] The compound can be made into a paste with concentrated hydrochloric acid, as metal halides, being volatile, give better results. [5] Different flames can be tried to verify the accuracy of ...
Hexabromocyclododecane (HBCD or HBCDD) is a ring consisting of twelve carbon atoms with six bromine atoms tied to the ring. The commercially used HBCD is in fact a mixture of different isomers. HBCD is toxic to water-living organisms. The UNEP Stockholm Convention has listed HBCD for elimination, but allowing a temporary exemption for the use ...
This char layer is much harder to burn and prevents further burning. [8] [9] Intumescents: These types of retardant materials incorporate chemicals which cause swelling behind the protective char layer, providing much better insulation. They are available as plastic additives, and as paints for protecting wooden buildings or steel structures.
A way to stop spreading of the flame over the material is to create a thermal insulation barrier between the burning and unburned parts. [14] Intumescent additives are often employed; their role is to turn the polymer surface into a char, which separates the flame from the material and slows the heat transfer to the unburned fuel. Non ...
Polybrominated diphenyl ethers or PBDEs, are a class of organobromine compounds that are used as flame retardants.Like other brominated flame retardants, PBDEs have been used in a wide array of products, including building materials, electronics, furnishings, motor vehicles, airplanes, plastics, polyurethane foams, [1] and textiles.
A thermal burn is a type of burn resulting from making contact with heated objects, such as boiling water, steam, hot cooking oil, fire, and hot objects. Scalds are the most common type of thermal burn suffered by children, but for adults thermal burns are most commonly caused by fire. [ 2 ]
Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine. This can be seen from the standard electrode potentials of the X 2 /X − couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V).
Materials that will not burn under typical fire conditions (e.g., carbon tetrachloride, silicon dioxide, perfluorohexane, water), including intrinsically noncombustible materials such as concrete, stone, and sand. Materials that will not burn in air unless exposed to a temperature of 820 °C (1,500 °F) for more than 5 minutes.