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Nitric acid structure

Red lead is insoluble in water. Like lead(II) oxide it can readily be reduced to lead. The structure of the solid, as the systematic name suggests, consists of two interpenetrating oxide structures, in which each Pb atom is surrounded octahedrally by six oxygen atoms, and each Pb" by three (pyramidal) oxygen atoms, the oxygen atoms being shared between these two units of structure. With dilute nitric acid the lead(ll) part dissolves, and the lead(IV) part precipitates as lead(IV) oxide ... [Pg.195]

Arsenic dissolves in concentrated nitric acid forming arsenicfV) acid, H3ASO4, but in dilute nitric acid and concentrated sulphuric acid the main product is the arsenic(III) acid, HjAsOj. The more metallic element, antimony, dissolves to form the (III) oxide Sb O, with moderately concentrated nitric acid, but the (V) oxide Sb205 (structure unknown) with the more concentrated acid. Bismuth, however, forms the salt bismulh(lll) nitrate Bi(N03)3. 5H,0. [Pg.212]

Dinitrogeri pentoxide is the anhydride of nitric acid and is prepared by removing water from pure nitric acid by means of phosphorus (V) oxide. It is a crystalline solid having the ionic structure of (N02) (N03) , nitronium nitrate (the nitronium ion is mentioned later). It decomposes above 273 K, thus ... [Pg.234]

The chemical properties of nitric acid require us to consider the structure first. The vapour of pure nitric acid (i.e. anhydrous) is probably composed of molecules of hydrogen nitrate , which structurally is a resonance hybrid of such forms as ... [Pg.240]

In liquid nitric acid, hydrogen bonding gives a loose structure similar to that of hydrogencarbonate ions. However, although pure nitric acid does not attack metals readily and does not evolve carbon dioxide from a carbonate, it is a conducting liquid, and undergoes auto-ionisation thus ... [Pg.240]

Related studies have been made using perchloric acid. From mixtures of anhydrous nitric and perchloric acids in the appropriate proportions, Hantzsch " claimed to have isolated two salts whose structures supported his hypothesis concerning the nature of nitric acid in strong mineral acids. He represented the formation of the salts by the following... [Pg.14]

There is increasing evidence that the ionisation of the organic indicators of the same type, and previously thought to behave similarly, depends to some degree on their specific structures, thereby diminishing the generality of the derived scales of acidity. In the present case, the assumption that nitric acid behaves like organic indicators must be open to doubt. However, the and /fp scales are so different, and the correspondence of the acidity-dependence of nitration with so much better than with Hg, that the effectiveness of the nitronium ion is firmly established. The relationship between rates of nitration and was subsequently shown to hold up to about 82 % sulphuric acid for nitrobenzene, />-chloronitrobenzene, phenyltrimethylammonium ion, and p-tolyltrimethylammonium ion, and for various other compounds. ... [Pg.22]

The isomer proportions for the nitration of the chlorotoluenes, to be expected from the additivity principle, have been calculated from the partial rate factors for the nitration of toluene and chlorobenzene and compared with experimental results for nitration with nitric acid at o °C. The calculated values are indicated in brackets beside the experimental values on the following structural formulae. In general, it can be... [Pg.184]

Davies and Warren" found that when 1,4-dimethylnaphthalene was treated with nitric acid in acetic anhydride, and the mixture was quenched after 34 hr, a pale yellow solid with an ultraviolet spectrum similar to that of a-nitro-naphthalene was produced. However, if the mixture was allowed to stand for 5 days, the product was i-methyl-4 nitromethylnaphthalene, in agreement with earlier findings. Davies and Warren suggested that the intermediate was 1,4-dimethyl-5 nitronaphthalene, which underwent acid catalysed rearrangement to the final product. Robinson pointed out that this is improbable, and suggested an alternative structure (iv) for the intermediate, together with a scheme for its formation from an adduct (ill) (analogous to l above) and its subsequent decomposition to the observed product. [Pg.222]

Lewis structures frequently contain atoms that bear a positive or negative charge If the molecule as a whole is neutral the sum of its positive charges must equal the sum of Its negative charges An example is nitric acid HNO3... [Pg.17]

Like nitric acid each of the following inorganic compounds will be frequently encountered in this text Calculate the formal charge on each of the atoms in the Lewis structures given... [Pg.19]

Electron Delocalization in the Conjugate Base With a of —1 4 nitnc acid is almost completely ionized m water If we look at the Lewis structure of nitric acid m light of what we have said about inductive effects we can see why The N atom m nitric acid IS not only electronegative m its own right but bears a formal charge of +1 which enhances its ability to attract electrons away from the —OH group... [Pg.42]

Treatment of biphenyl (see Section 11 7 to remind yourself of its structure) with a mixture of nitric acid and sulfuric acid gave two principal products both having the molecular formula C12H9NO2 What are these two products ... [Pg.497]

With iodine in carbon tetrachloride, 4-methylpyrazole affords a deep-red oil for which the structure (266) has been proposed. Nitric acid, silver nitrate and iodine together convert pyrazole into 1,3,4-triiodopyrazole (267 = R" = I, = H). The fV-iodopyrazoles are... [Pg.234]

Nitration of a series of methyl-1,2-benzisoxazoles was studied by Tahkar and Bhawal using fuming nitric acid and sulfuric acid in acetic acid at 100 °C. 3-Methyl-1,2-benzisoxazole gave a mixture of 5-nitro- and 5,7-dinitro-3-methyl-l,2-benzisoxazole, with the 5-nitro isomer predominant. The product obtained from 3,5-dimethyl-1,2-benzisoxazole was the 4-nitro derivative and not the 7-nitro compound as proposed by Lindemann (26LA(449)63). The synthesis of the 7-nitro compound by an alternative method was used as structural proof. Two products were obtained from 3,6-dimethyl-l,2-benzisoxazole and these were the 5-nitro and 5,7-dinitro derivatives. 3,7-Dimethyl-l,2-benzisoxazole was converted into the 5-nitro derivative (Scheme 25) (77lJC(B)l06l). [Pg.23]

Constitution. Hydrastine contains two methoxyl groups and a methylenedioxy-group, and behaves as a tertiary base. The first insight into the inner structure of the base was obtained when Freund and Will showed that with dilute nitric acid it undergoes hydrolytic oxidation, yielding opianic acid and a new base hydrastinine, CiiHigOgN. This reaction is analogous with the similar hydrolytic oxidation of narcotine (p. 201) to opianic acid and cotarnine and hydrastinine is allied to cotarnine and can be prepared from it. [Pg.163]

The assumption of these conjugated double bonds makes possible a tetracyclic nucleus which accords with the suggestion previously made by the authors that these alkaloids might be structurally related to the diterpenes. It may also be noted that one of the nitric acid oxidation products of pseudaconitine has been recorded as unexpectedly giving a pyrrole reaction on destructive distillation. ... [Pg.693]

Nitric oxide is the simplest thermally stable odd-electron molecule known and, accordingly, its electronic structure and reaction chemistry have been very extensively studied. The compound is an intermediate in the production of nitric acid and is prepared industrially by the catalytic oxidation of ammonia (p. 466). On the laboratory scale it can be synthesized from aqueous solution by the mild reduction of acidified nitrites with iodide or ferrocyanide or by the disproportionation of nitrous acid in the presence of dilute sulfuric acid ... [Pg.445]

Dinitrogen pentoxide, N205, when bubbled into water can form nitric acid. Its skeleton structure has no N—N or O—O bonds. Write its Lewis structure. [Pg.192]

In this reaction, called bromination, one of the hydrogen atoms has been replaced by a bromine atom. Notice that the double bond structure is not affected—this is not an addition reaction. Nitric acid causes a similar reaction, called nitration ... [Pg.344]

Alkali fusion of the metabolite furnished p-hydroxybenzoic acid in good yield as the only isolable product. Vigorous nitric acid oxidation of M gave a high yield of picric acid. Both degradation products must have arisen from the same site, which can be represented by part structure V. While positions 3 and 5 are probably unsubstituted, the vigorous nature of the degradations allows that those at 2 and 6 could bear carbon atoms. [Pg.89]

Pure TeNMe is said to be colorl, but becomes yellow on contact with w, due to hydrolysis to TNMe (Ref 5). Mp 14.2° (Ref 26) bp 125.7° (Ref 10) d at 25°, 1.62294g/cc RI at 25°, 1.43822 (Ref 18). The dipole moment is essentially zero, indicating the structure to be symmetric, instead of (02N)sC0N0 as had been postulated to account for its reactivity (Ref 18) CA Registry No 509-14-8 Historical It was first prepd by the action of nitric acid on TNMe (Ref 2). This reaction is the basis of large scale prepn in which acetylene is nitrated to TNMe and the latter treated with an excess of nitric acid to give TeNMe (Ref 26). [Pg.101]

The reflux of aqueous Pu(IV) solutions containing <6 M HNO3 produces polymer precipitates that are resistant to subsequent dissociation and dissolution in nitric acid. Eapid aging of the Pu(IV) polymer to form a PuC -like structure is responsible for the unusually stable polymer. Comparative studies under nonreflux conditions show that polymer does not form at concentrations of HNO3 >3 M. [Pg.232]

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. [Pg.616]

Newton s second law, L0 nickel, 49, 665 nickel arsenide structure, 201 nickel surface, 189 nickel tetracarbonyl, 665 nickel-metal hydride cell, 520 NiMH cell, 520 nitrate ion, 69, 99 nitration, 745 nitric acid, 629 nitric oxide, 73, 629 oxidation, 549 nitride, 627 nitriding, 208 nitrite ion, 102 nitrogen, 120, 624 bonding in, 108 configuration, 35 photoelectron spectrum, 120... [Pg.1035]


See other pages where Nitric acid structure is mentioned: [Pg.15]    [Pg.17]    [Pg.20]    [Pg.260]    [Pg.138]    [Pg.525]    [Pg.17]    [Pg.18]    [Pg.18]    [Pg.467]    [Pg.1276]    [Pg.55]    [Pg.296]    [Pg.51]    [Pg.63]    [Pg.634]    [Pg.461]    [Pg.74]    [Pg.245]    [Pg.458]    [Pg.833]    [Pg.211]    [Pg.219]   
See also in sourсe #XX -- [ Pg.417 , Pg.418 ]

See also in sourсe #XX -- [ Pg.471 , Pg.472 ]

See also in sourсe #XX -- [ Pg.646 ]




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