Nitric acid physical properties

Table 1 Hsts some of the physical properties of duoroboric acid. It is a strong acid in water, equal to most mineral acids in strength and has a p p o of —4.9 as compared to —4.3 for nitric acid (9). The duoroborate ion contains a neady tetrahedral boron atom with almost equidistant B—F bonds in the sohd state. Although lattice effects and hydrogen bonding distort the ion, the average B—F distance is 0.138 nm the F—B—F angles are neady the theoretical 109° (10,11). Raman spectra on molten, ie, Hquid NaBF agree with the symmetrical tetrahedral stmcture (12).

Lead Fluoride. Lead difluoiide, Pbp2, is a white oithorhombic salt to about 220°C where it is transformed into the cubic form some physical properties ate given in Table 1. Lead fluoride is soluble in nitric acid and insoluble in acetone and ammonia. It is formed by the action of hydrofluoric acid on lead hydroxide or carbonate, or by the reaction between potassium fluoride and lead nitrate. 

Table 1. Physical Properties of Nitric Acid Solutions at 20°C...

Physical properties of hexachloroethane are Hsted in Table 11. Hexachloroethane is thermally cracked in the gaseous phase at 400—500°C to give tetrachloroethylene, carbon tetrachloride, and chlorine (140). The thermal decomposition may occur by means of radical-chain mechanism involving -C,C1 -C1, or CCl radicals. The decomposition is inhibited by traces of nitric oxide. Powdered 2inc reacts violentiy with hexachloroethane in alcohoHc solutions to give the metal chloride and tetrachloroethylene aluminum gives a less violent reaction (141). Hexachloroethane is unreactive with aqueous alkali and acid at moderate temperatures. However, when heated with soHd caustic above 200°C or with alcohoHc alkaHs at 100°C, decomposition to oxaHc acid takes place. 

Figure 8.1 Effect of pH on corrosion of 1100-H14 alloy (aluminum) by various chemical solutions. Observe the minimal corrosion in the pH range of 4-9. The low corrosion rates in acetic acid, nitric acid, and ammonium hydroxide demonstrate that the nature of the individual ions in solution is more important than the degree of acidity or alkalinity. (Courtesy of Alcoa Laboratories from Aluminum Properties and Physical Metallurgy, ed. John E. Hatch, American Society for Metals, Metals Park, Ohio, 1984, Figure 19, page 295.)...

Nitric oxide and NjO are direct intermediates in the denitrification pathway, the reduction of NO3 to Nj. Reduction to Nj is often incomplete, so that both NjO and Nj are equally important end products of denitrification, the ratio of NjO/Nj production being determined by soil physical properties. For example, NjO is the main end-product in acid soils, whereas low redox potentials and high organic matter content favour the further reduction to Nitric... 

Physical Properties. According to Lagowski (Ref 32), X-ray analysis of a single crystal of nitric acid shows a monoclinic unit cell (symmetry P21/a-Cfh) the following dimensions a=16.23, b=8.57, and c=6.3lA, and 0=90°. The unit cell contains 16 molecules, and the calc d is 1.895g/cc at —41.6°... 

Nitric acid solutions, physical properties of, 17 172t... 

Elemental composition Cu 57.47%, C 5.43%, H 0.91%, 0 36.18%. Both malachite and azurite may be identified by x-ray analysis and analyzed qualitatively using physical properties such as refractive index and density. For quantitative analysis, the compound may he digested in nitric acid and analyzed for copper by various instrumental methods (see Copper.)... 

Elemental composition Ga 69.24%, P 30.76%. Gallium phosphide may be characterized hy its physical and electronic properties. It may also he analyzed hy various x-ray methods. Gallium may he measured hy AA and ICP spectrophotometry following digestion with nitric acid or aqua regia and appropriate dilution (See Gallium). 

Elemental composition Pb 64.11%, Cr 16.09%, O 19.80%. Lead chromate may be identified from its physical properties and x-ray crystallography. Lead and chromium can be measured in a nitric acid solution of the compound by AA, ICP, and other instrumental methods. (See Lead.)... 

Elemental composition Pb 68.32%, S 10.57%, O 21.10%. the solid crystalline powder or the mineral anglesite may be characterized by x-ray techniques and physical properties. Lead can be analyzed in the sohd compound or its nitric acid extract by various instrumental techniques (See Lead). 

Elemental composition Li 46.45%, 0 53.55%. The oxide may he identified from its physical properties and characterized by x-ray analysis. Lithium composition in the oxide may be determined by analyzing the nitric acid extract by AA or ICP (See Lithium). 

Elemental composition 86.96%, C 10.41%, H 2.62%. The compound can be identified from its physical properties, elemental analyses and infrared spectra. Mercury can be identified by cold-vapor AA or ICP/AES after cautious extraction with nitric acid. In a suitable organic solvent, it may be analyzed by GC/MS. The characteristic ions are 217, 215, 202, 200, 232 and 230. 

Elemental composition Hg 76.39%, N 5.33%, 0 18.28%. The salt is dissolved in dilute nitric acid and analyzed for mercury (see Mercury). The compound is blackened by ammonia and caustic alkali solutions. It may be identified by physical and x-ray properties. 

Elemental composition Mo 45.70%, F 54.30%. The compound may be identified from its physical properties. Molybdenum may be analyzed by AA or ICP in an acid extract of the compound following digestion with nitric acid. 

Elemental composition Mo 35.12%, Cl 64.88%. Molybdenum pentachloride may be identified from its physical properties and the products it forms in various reactions. The molybdenum content may be measured by flame or fur-nace-AA or ICP/AES measurement following digestion with nitric acid and appropriate dilution. 

Elemental composition Ni 22.85%, C 46.75%, H 5.49%, O 24.91%. The compound may be characterized by its physical properties, elemental analysis, and by IR, UV and NMR spectra and x-ray diffraction data. A benzene or chloroform solution may be injected directly into a GC column and may be identified from its mass spectra. The characteristic mass ions for its identification by GC/MS are 58, 60, 100, 257. The aqueous solution or the nitric acid extract may be analyzed either by flame or furnace AA, or by ICP-AES to determine nickel content. 

Elemental composition Ni 78.58%, O 21.42%. Nickel may be analyzed in a diluted solution of the oxide in nitric acid by AA, ICP and other instrumental methods. The oxide may be identified from its physical properties and by x-ray diffraction. 

Elemental composition Ni 64.68%, S 35.33%. The compound may be identified by x-ray crystallographic and physical properties. Nickel may be measured in nitric acid extract by AA or ICP methods (See Nickel). 

Nitrogen dioxide can be identified by color, odor, and physical properties. It is dissolved in warm water and converted to nitric acid. The latter may be measured by acid-base titration or from analysis of nitrate ion by nitrate ion-specific electrode or by ion chromatography. Alternatively, nitrogen dioxide may be passed over heated charcoal to produce nitrogen and carbon dioxide that may be analysed by GC-TCD or GC/MS (See Nitrogen, Analysis). The characteristic masses for N2 and CO2 formed for their identification are 28 and 44, respectively. 

Exists in two adotropic modifications. Crystalline sihcon is made up of grayish-black lustrous needle-hke crystals or octahedral platelets cubic structure Amorphous sdicon is a brown powder. Other physical properties are density 2.33g/cm3 at 25°C melts at 1,414°C high purity liquid silicon has density 2.533 g/cm at its melting point vaporizes at 3,265°C vapor pressure 0.76 torr at 2,067°C Mohs hardness 6.5. Brinell hardness 250 poor conductor of electricity dielectiric constant 13 critical temperature 4°C calculated critical pressure 530 atm magnetic susceptibility (containing 0.085%Fe) 0.13x10 insoluble in water dissolves in hydrofluoric acid or a mixture of hydrofluoric and nitric acids soluble in molten alkalies. 

Elemental composition Sn 78.77%, 0 21.23%. Tin(IV) oxide can be identified by physical properties and x-ray diffraction. Tin content may be determined by various instrumental techniques in an acid solution of the oxide (See Tin). The compound is solubilized by digestion with nitric acid or aqua regia and diluted appropriately. 

Elemental composition Ti 59.95%, O 40.05%. The oxide may be identified by its physical properties and by x-ray methods. Titanium content may be measured by AA or ICP. The compound is digested in nitric acid or aqua regia, solubdized, and diluted sufficiently for metal analysis. 

The ultimate composition of ceria was established many years after its isolation by C, G, Mosander, a Swedish surgeon, chemist and mineralogist, who was for a time assistant to Berzelius, During the period 1839-1841, Mosander thermally decomposed a nitrate obtained from ceria and treated the product with dilute nitric acid. From the resulting solution, he then isolated first a new earth, "lanthana", and then another new earth, "didymia" (the twin brother of lanthana), of similar chemical but slightly different physical properties, (Figure 1)... 

Is fluorine an element 1 Since fluorine had never been previously isolated, it remained for H. Moissan to prove that the gas he found to be liberated at the positive pole is really fluorine. Many of its physical and chemical properties, as will be shown later, agree with those suggested by the analogy of the fluorides with the chlorides, bromide, and iodides. It was found impossible to account for its properties by assuming it to be some other gas mixed with nitric acid, chlorine, or ozone or that it is a hydrogen fluoride richer in fluorine than the normal hydrogen fluoride. 

---