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Phosphorus pentabromide is a reactive, yellow solid of formula P Br 5, which has the structure [PBr 4] + Br − (tetrabromophosphonium bromide) in the solid state but in the vapor phase is completely dissociated to PBr 3 and Br 2.
Phosphorus pentafluoride is a Lewis acid.This property is relevant to its ready hydrolysis. A well studied adduct is PF 5 with pyridine.With primary and secondary amines, the adducts convert readily to dimeric amido-bridged derivatives with the formula [PF 4 (NR 2)] 2.
Moreover, because the acidic or basic drain cleaners themselves are washed down the drain, this contributes to pollution in the water supply. Drain cleaners usually contain a strong base such as sodium hydroxide that decomposes hair and converts fats into water-soluble products. The reaction is exothermic, releasing heat to soften the fats.
An aerogel material can range from 50% to 99.98% air by volume, but in practice most aerogels exhibit somewhere between 90 and 99.8% porosity. [12] Aerogels have a porous solid network that contains air pockets, with the air pockets taking up the majority of space within the material. [13]
The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. [2] Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock mechanism in firearms; and spark testing ferrous metals.
Note that the especially high molar values, as for paraffin, gasoline, water and ammonia, result from calculating specific heats in terms of moles of molecules. If specific heat is expressed per mole of atoms for these substances, none of the constant-volume values exceed, to any large extent, the theoretical Dulong–Petit limit of 25 J⋅mol ...
The site and extent of absorption of inhaled gases and vapors are determined by their solubility in water. Absorption is also dependent upon air flow rates and the partial pressure of the gases in the inspired air. The fate of a specific contaminant is dependent upon the form in which it exists (aerosol or particulate).
Antimony is a silver-white solid with a blue tint and a brilliant lustre. It is stable in air and moisture at room temperature. Antimony has a density of 6.697 g/cm 3, and is moderately hard (MH 3.0; about the same as copper). It has a rhombohedral crystalline structure (CN 3). Antimony melts at 630.63 °C and boils at 1635 °C.