Nitric acids

This acid has never been used in a systematic stu in cationic polymerisation. This is not surprising, given the low stability of pure HNO3. Homoconjugation of this acid with its anion has been reported  

Tazuke et al. investigated briefly the role of this initiator in the polymerisation of N-vinylcarbazole in the context of a wider study involving metal salts as promoters. They found that aqueous nitric acid in dioxane was able to induce the polymerisation of this very sensitive monomer. Concentrations of 10 to 10 M gave 50% conversion in several hours. No useful speculation can be offered about the meaning of these results considering the very odd medium used and the rvelldcnown idiosyncra of the monomer. The pK of this acid is 8.9 in acetonitrile and 10.1 in acetic acid  

The strength of sulphuric acid is usually considered as intermediate between those of HCl and HBr. Thus, the following pK values have been determined or interpolated 7.0 in acetic acid , 7.25 in acetonitrile and about 9.5 in 1,2-dichloroethane. This acid exists essentially as monomer in non-aqueous solvents, but has a strong affinity for its anion as shown in homoconjugation studies in nitromethane acetonitrile (pKhbJ —3 ) and in propylene carbonate  

Despite its fame as the first initiator used in cationic polymerisation, sulphuric acid has not frequently been used for fundamental studies in this field. Ite low vapour pressure hinders proper purification procedures even in high vacuum, and its limited solubflity in the solvents currently used for these investigations is another serious drawback. While alkenes are only oligomerised by this acid, aromatic monomers can give high polymers under suitable conditions. Our present discussion will be limited to the only system investigated in depth, i.e. the polymerisation of stjrene. 

Tsuda and Asami and Tokura reported the polymerisation of styrene by sulphuric acid in methylene chloride and sulphur dioxide respectively, but did not cany out any extensive kinetic or mechanistic study of these systems. It was Pepper and his collaborators w4io undertook the task of looking into this proce methodi-cally Although previously reviewed this woric is worth rediscussing. 

Nitric acid vapour pyrolyzes at a measurable rate above 100 °C, decomposition proceeding in accordance with the stoichiometric equation 

The following elementary steps in combination with (45, —45) represent a mechanism which satisfactorily describes observations at 1 atm  

Assuming a steady-state concentration of N03, the reaction scheme leads to the rate expression 

Rate coefficients of elementary steps in the thermal decomposition of HN03 are summarized in Table 21. 

RATE COEFFICIENTS OF ELEMENTARY STEPS IN THE DECOMPOSITION OF HNO3 

Nitric acid is a strongly acidic, corrosive liquid that is produced commercially by the oxidation of ammonia and subsequent reaction of the oxidation products with water. Pure nitric acid is colorless. The characteristic yellow-brown color generally associated with concentrated solutions is due to dissolved nitrogen dioxide91. 

Nitric acid is an active compound and its salts, the nitrates, are found in all fertile soils. The alchemists obtained nitric acid by heating alum and copper sulfate with nitrate in a retort. Owing to its powerful corrosive action, they named it aqua fortis or strong water. 7 It is also known as azotic acid, hydrogen nitrate and nitryl hydroxide. 

Nitric acid reacts with all metals except the precious metal series and certain alloys. Although chromium, iron and aluminum readily dissolve in dilute nitric acid, the concentrated acid forms a metal oxide layer that protects (passivates) the metal from further oxidation53. 

Nitric acid. Red atoms are oxygen white atom is hydrogen and blue atom is nitrogen. Gray sticks indicate double bonds, publishers 

The chemical nature and composition of nitric acid were first determined in 1784 by the English chemist and physicist Henry Cavendish (1731-1810). Cavendish applied an electric spark to moist air and found that a new compound-nitric acid-was formed. Cavendish was later able to determine the acid s chemical and physical properties and its chemical composition. The method of preparation most commonly used for nitric acid today was one invented in 1901 by the Russian-born German chemist Friedrich Wilhelm Ostwald (1853-1932). The Ostwald process involves the oxidation of ammonia over a catalyst of platinum or a platinum-rhodium mixture. 

nitric acid is one of the most important chemical compounds used in industry. It ranks number thirteen among all chemicals produced in the United States each year. In 2005, about 6.7 million metric tons (7.4 million short tons) of the compound were produced in the United States. 

Alchemists called nitric acid aqua fortis, a term that means strong water.  

Nitric acid is a component of acid rain, a form of pol- 

Nitric Acid. The freezing-point depression by nitric acid of a eutectic perchloric acid-water system is only one-half of the depression caused by other acids of equal molalities (HCl, HCIO3, H2SO4). Since no solid solution of HNO3 is formed, it was concluded that nitric acid exists in dimeric form in eutectic perchloric acid. Raman and u.v. spectra provide corroborative evidence. The first cryoscopic study of DNO3has been reported and allows comparison to be made with HN08. For example, the m.p. of DNOg is 

New measurements of the gas-phase u.v. absorption spectrum of nitric acid vapour have been used in conjunction with semi-empirical LCAO-SCF calculations (including Cl) to help define the lower electronic states of HNOg. CH3NO2 and C2H6NO2 were also studied and the results are presented in Table 9. It was concluded that the electronic transitions on these 

Molecule Observed Calculated Observed Calculated Transition 

The kinetics and mechanism of oxalate ion decarboxylation in nitrate melts have been investigated  

The dependence of the reaction rate on the flow rate of the purge gas (Ar) and of the initial COg concentration was established. The NO ion was shown to be the oxidizing species in the decarboxylation process. 

Nitric Acid. 0-Multilabelled anhydrous HNO3 (89 atom.% has been 

Following earlier studies of molal freezing-point depression in eutectic aqueous perchloric acid (M. Ardon and L. Halicz, Inorg. Chcm., 1973,12, 1903), similar investigations in eutectic aqueous trifluoroacetic add now show that nitric add dimerizes in both of these media. In the light of these results, dimerization in aqueous solutions of nitric acid itself, in concentrations of ca. SmolT, is considered to be a distinct possibility, but no information on the structure and bonding of the dimer is yet available. 

1 Nitric Acid, Sodium Chiorite (Biack Oxide) 

This method is intended for relatively pure copper alloys containing more than 95% copper. It tends to leave a stable surface. It is not recommended for use wifli adhesives fliat contain chlorides or for hot bonding to polyefliylene. 

Immerse in the etching solution for 30 s at room temperature. The solution is made by mixing 30 parts of nitric acid (70% technical) and 90 parts of water, all by volume 

Rinse in running water and transfer immediately to the next solution without allowing 

Immerse for 2—3 min at 93—102 °C in the bath shown in Table 6.9. This solution should not be boiled 

For many years nitric acid was made by the reaction of sulfuric acid and saltpeter (sodium nitrate), but this method is no longer used. 

Direct oxidation of ammonia is now the only process. 2.1.1 Reactions 

Nitric acid is now manufactured by combusting ammonia in air in the presence of a (platinum or other noble metal) catalyst, and the nitrogen oxides thus formed are oxidized further and absorbed in water to form nitric acid. 

In this process (Fig. 1), the reactor contains a rhodium-platinum catalyst (2 to 10% rhodium) as wire gauzes in layers of 10 to 30 sheets at 750 to 920°C, 100 psi, and a contact time of 3 X 10 4 second. After cooling, the product gas enters the absorption tower with water and more air to oxidize the nitric oxide and hydrate it to nitric acid in water. Waste gases contain nitric oxide or nitrogen dioxide, and these are reduced with hydrogen or methane to ammonia or nitrogen gas. Traces of nitrogen oxides can be 

Nitric acid is predominantly used for fertilizer manufacture. It also finds use in the manufacture of adipic acid, nitroglycerin, nitrocellulose, ammonium picrate, trinitrotoluene, nitrobenzene, silver nitrate, and various isocyanates. 

CHEMICAL NAME = nitric acid CAS NUMBER = 7697-37-2 MOLECULAR FORMULA = HN03 MOLAR MASS = 63.0 g/mol COMPOSITION = 14(1.6%) N(22.2%) 0(76.2%) 

Nitric acid can be prepared by several methods, but the primary method is by the oxidation of ammonia using the Ostwald method, which was named for Wilhelm Ostwald (1853-1932). The Ostwald method enabled the Germans to produce explosives in World War 

Nitric acid is used for nitrating numerous other compounds to produce nitrates. Nitric acid is used to produce adipic acid (C6H4O10), which is used in the production of nylon (see Nylon). In this process, cyclohexane is oxidized to a cyclohexanol-cyclohexanone mixture. Cyclohexanol and cyclohexanone are then oxidized with nitric acid to adipic acid. 

Additional uses of nitric acid are for oxidation, nitration, and as a catalyst in numerous reactions. Salts of nitric acid are collectively called nitrates, which are soluble in water. Nitric acid is used in the production of many items such as dyes, pharmaceuticals, and synthetic fabrics. It is also used in a variety of processes including print making. 

Nitric acid is used extensively in the metal industries. Nitric acid dissolves most metals and is used to separate gold from silver in assaying and metal refining operations. Some 

The detection of nitric acid (HNO3) in the ozonosphere by Murcray et al. (1968) and the deduced number mixing ratios ( 3 x 10 ) provide us with very valuable information. 

Nitric acid may be formed by the pair of reactions (see Leighton 1961 Nicolet 1965)  

It should also be pointed out that the water vapour mixing ratios may be different from those assumed here. 

It can, of course, not be excluded that additional processes must be considered in the HNO3 formation. A possibility for more OH and HO2 are the processes 

Reaction (27) is spin forbidden, but a quantum yield as low as 10 may be enough to make it of interest. The reason for this is that O ( S) is much less rapidly deactivated than O ( D)  

Chlorosulfonic acid reacts with 100% nitric acid (prepared by distillation of concentrated nitric acid and 30% oleum) to give nitryl chloride 6 (Equation 13). Chlorosulfonic acid (one equivalent) is added dropwise to stirred 100% nitric acid at 0 °C, and after half an hour at RT, nitryl chloride distils as a pale yellow liquid (bp —17 to — 18 C). Pure nitryl chloride is a colourless gas and this reaction provides the best synthetic route to the compound.  

Composition Commercial concentrated nitric acid contains about 68-70% nitric acid and 

30-32% water, normality 15-16 white fuming nitric acid contains 97.5% nitric acid, less than 2% water, and less than 0.5% nitrogen oxides by weight and red fuming nitric acid contains more than 86% acid, less than 5% water, 6-15% nitrogen oxides by weight. 

Synonyms aquafortes acotic acid hydrogen nitrate 

Nitric acid is one of the most widely used industrial chemicals. It is employed in the production of fertilizers, explosives, dyes, synthetic fibers, and many inorganic and organic nitrates and as a common laboratory reagent. 

Colorless liquid, yellow to brown, due to the presence of dissolved nitrogen dioxide, NO2, formed as a result of slow photochemical decomposition of nitric acid catalyzed by sunlight fumes in moist air boils at 86° C (186°F) [68% acid boils at 121.6°C (250°F)] freezes at —42°C (—43°F) density 1.413 (70% acid) and 1.513 (100% acid) at 20°C (68°F) infinitely miscible with water. 

Perform experiments with concentrated nitric acid in a fume cupboard-, wear gloves and eye protection. 

Preparation of Nitric Acid from Saltpetre. [Perform the experiment in a fume cupboard ) Assemble a setup as shown in Fig. 80. 

Put 10 g of sodium nitrate into retort 1 and pour in 10 ml of a 96% sulphuric acid solution. Close tubulature 2 with an asbestos stopper. Fill vessel 3 for cooling receiver 4 with water and ice. Carefully heat the retort. What occurs How can you explain the appearance of brown vapour in the retort When 4-6 ml of nitric acid are collected in receiver 4, stop heating the retort. Keep the prepared nitric acid for the following experiment. 

Explain from the standpoint of the law of mass action why dry sodium nitrate (saltpetre) and a concentrated sulphuric acid solution are taken to prepare a concentrated nitric acid solution. Why does the reaction mixture have to be heated, but carefully What are the boiling points of sulphuric and nitric acids How do nitric acid solutions of various concentrations behave when heated W hat is the composition of an azeotropic mixture of nitric acid with water  

Properties. [Perform the experiments in a fume cupboard]) 1. Pour 1-2 ml of freshly prepared concentrated nitric acid into a porcelain bowl. Add one or two drops of concentrated sulphuric acid and carefully add two or three drops of pure turpentine to it with the aid 

Form Supplied in clear colorless liquid (69-71% in H2O) fuming nitric acid is a colorless to pale yellow liquid, HNO3 content 90% widely available. 

Preparative Method anhydrous nitric acid can be prepared by distilling fuming nitric acid from an equal volume of concentrated sulfuric acid. 

Kathlyn A. Parker Mark W. Ledeboer Brown University, Providence, RI, USA 

Nitric acid holds an important place in the history of organic synthesis. It is used primarily for the nitration of organic molecules and to effect a wide variety of oxidative transformations. The advantage of nitric acid as a reagent is that it allows simple and straightforward isolation of products. However, it is not a very selective oxidant. 

Nitration of Simple Aromatic Systems. Nitration of aromatics has been studied extensively. The mechanism by which ni- 

In contact with water, it is destroyed, giving rise, like the preceding acid, to nitric acid, and deutoxide of nitrogen. Thus, 3 NO,=2 NO +NO,. As it undergoes the same change in contact with all bases hitherto tried, its salts are unknown. Alo ig with pure nitric acid, it forms the orange-fuming nitric acid of the shops, often called nitrous acid. 

The hydrated acid, HO, NO, or H, NO, is the substance commonly called nitric acid. It is best prepared by the distillation of a mixture of equal weights of hydrated sulphuric acid, or oil of vitriol, and of nitre or saltpetre, the nitrate of potash. The salt in coarse powder being introduced into a plain retort, 

The retort is then placed in a sand-bath over the lamp, and cautiously heated, till the acid begins to drop into the receiver, which is to be surrounded with cold water. As the nitre generally contains a little sea-salt, the first portions of acid which distil are impure, containing chlorine and nitrous acid but they serve to wash quite clean the neck of the retort, on which some sulphuric acid is commonly to be found, in spite -of all our care, as well as traces of the powdered nitre. It is best, therefore, to collect the first portion, say the 

The pre.sence of nitric acid in a liquid is best ascertained by adding pure oil of vitriol, and then a drop or two of solution of green vitriol. If nitric add be present, a red or brown colour will appear where the two liquids meet and by this test of nitric acid may be detected. 

Pure nitric acid ought to he entirely volatile and when diluted with distilled water, to give no precipitate with the salts of baryta, or of silver. 

The purpose of this chapter is to describe the technology and economics of production of nitric acid and nitrates (except potassium nitrate, which is covered in Chapter 15) and the production of ammonium salts for fertilizer use (other than ammonium phosphates, which are covered in Chapter 12). The chapter also includes nitric acid and nitrate technologies developed in Russia and other countries of Eastern and Central Europe. The Commonwealth of Independent States (QS) was the largest producer of nitric acid, nitrates, and other fertilizers in that area [1,2,31, and all original technologies in the CIS were developed solely by the State Institute of Nitrogen Industry (GIAP). 

The proportionate declirie iri the cbnsumpffofTof ammonium nitrate has resulted from massive development of urea production in developing countries and the introduction of complex fertili rs based on ammonium phosphates. However, considering the hi er nitrogen use efficiency of ammonium nitrate compared with urea, ammonium nitrate may be the more eco-nonnical nitrogen source in many situations. 

Nitric add is one of the oldest known chemicals. Three methods of production of nitric acid have been developed  

The first patent on ammonia oxidation wras issued to Khulman in 1839 in this case platinum was used as a catalyst to oxidize ammonia with air. The ammonia-oxidation method using a platinum catalyst qn a commercial scale, developed by Oswald and Brauer and first operated in Germany about 1908, is at present the principal industrial method of nitric acid producticxi. The main use for nitric acid is in fertiDzer production, mainly for ammonium nitrate as such or in compound fertilizers, nitrogen solutions, or mixed salts. About 75% of total nitric acid production is consumed for nitrate fertilizers, mainly as 509 5% concentration acid. Smaller fertilizer uses are for calcium and potassium nitrates. A primary use is in addulation of phosphate rock for production of nitrophosphates. Plant capacities for weak nitric acid i Bed for fertilizer production are in the range of 35 to 1,380 tpd althoi h capacities of 2,000 tpd have been designed. 

Poster Fibers Ptai Ester Plastics Pd amJdc Fibers Polyamide Plastics 

In this section, the physical and chemical properties of oxidizers commonly found in metal CMP slurries, such as nitric acid, ferric salts, hydrogen peroxide, iodates, permanganates, and chromates, are first described. The focus will then turn to their capability in material removal rate and their corrosion tendency of the metal films of interest. 

HNO3 mainly leads to a direct dissolution of copper into ions. 

FIGURE 7.1 Pourbaix diagram of copper-water system (from Ref. 1). 

Carpio and coworkers [4] supported this hypothesis via a potentiodynamic study of a set of HN03-containing slurries. The corrosion currents and potentials under both the static and the dynamic conditions were practically the same. This is consistent with the fact that there was no native copper oxide film formed because of the presence of these slurries. As a matter of fact, the corrosion currents decreased slightly upon abrasion of the copper surface. The contact between the metal surface and the abrasive pad may have limited the mass transport of chemicals to and from the copper surface. This was verified via an AC impedance measurement that showed the importance of the systems mass transport. It was also concluded that in a dissolution-controlled process, mechanical abrasion would not enhance the chemical corrosion rate or reduce the mass transport of reactants and/or products in the system. 

For laboratory experiments and sometimes in industry more expensive nitrating agents may be used, as for example solutions of nitric acid in inert organic solvents (chloroform, carbon tetrachloride, ether, nitromethane, etc.), or a solution of nitric acid in phosphoric or acetic acids or in acetic anhydride. The use of these nitrating agents may be of some practical value and will be discussed later on in detail. 

For nitrating on the laboratory scale, mixtures of nitric acid esters or acyl nitrates, e.g. acetyl nitrate CH3C0N03, and sulphuric acid may also be used. 

Several lesser known nitrating agents, which can find practical use on a laboratory scale are metal nitrates in the presence of acetic acid or acetic anhydride, described by Menke [2], tetranitromethane and hexanitroethane in an alkaline medium, used by Schmidt [3], Mid nitroguanidine in solution in sulphuric acid, used for the nitration of aromatic amines Mid phenols. 

Besides these direct methods of introducing nitro groups, several indirect methods are known that consist in the introduction of a group which can readily be substituted by a nitro group. In one of these which is widely used in the nitration of phenols, a compound is sulphonated and subsequently, by reaction with nitric acid, the sulpho group is replaced by the nitro group. 

In experimental work indirect methods of introducing nitro groups find wide application as, for example, the substitution of a halogen (iodine or bromine in an alkyl iodide or bromide) by the Nitro group, by means of silver nitrite (the Victor Meyer reaction), and the new modification of this method described recently by Komblum et al. [4, 4a], in which alkyl halides are reacted with sodium nitrite. 

Nicotine, absorbed dermally, is probably the cause of green tobacco sickness, a selflimited illness consisting of pallor, vomiting, and prostration, seen in men handling tobacco leaves in the field/ 

Nicotine is teratogenic in mice skeletal system malformations occurred in the offspring of pregnant mice injected subcutaneously with nicotine between days 9 and 11 of gestation/ It has also been found to cause behavioral changes in animals after experimental prenatal exposure/ 

The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) is 0.5 mg/ m with a notation for skin absorption. 

Friedman PA Poisoning and its management. In Petersdorf RG et al. (eds) Harrison s Principles of Internal Medicine, 10th ed, p 1271. New York, McGraw-Hill, 1983 

Gosselin RE, Smith RP, Hodge HC Clinical Toxicology of Commercial Products, Section HI, 5th ed, pp 311-314. Baltimore, MD, Williams Wilkins, 1984 

The quantum yield for photodissociation, reaction (14), is approximately 1 from 200 to 315 nrn (DeMore et al., 1997)  

At shorter wavelengths in the vacuum ultraviolet, the path to give O + HONO appears to become important. 

Donaldson et al. (1997) have proposed that absorption in the visible due to OH vibrational overtones could be important in the lower stratosphere at large solar zenith angles. Transfer of energy from the absorbing mode to the HO—NOz bond may then cause dissociation, as observed, for example, in HOC1 (e.g., 

TABLE 4.12 Absorption Cross Sections (Base e) for HN03 Vapor at 298 K  

Wavelength (nm) 102 r (cm2 molecule 1) Wavelength (nm) io2V (cm2 molecule 1) Wavelength (nm) 102n r (cm2 molecule 1) 

The photolysis of HONO2 in the near ultraviolet leads to the formation of OH and NO2 (2). 

The internal state distribution of the product 0H(X II) was probed by Jacobs et al. (38) using laser induced fluorescence. 

The rotational distribution has a peak at K = 6 and approaches zero at about K = 18. The only 3% of the available energy goes into rotation. The distribution deviates from that of the Boltzmann at lower K s. The vibrational population of v = 1 is less than 0.05. The and 3/2 were equally populated. The 

2-134 Partial Vapor Pressure of Sulfur Dioxide over 

2-155 Heat Capacity at Constant Pressure of Inorganic and Organic Compounds in the Ideal Gas State Fit to a 

2-179 Enthalpies and Gibbs Energies of Formation, Entropies, and Net Enthalpies of Combustion of Inorganic and 

2-183 Heats of Solution of Organic Compounds in Water (at Infinite Dilution and Approximately Room Temperature). 2-206 

In addition to their X-ray work on HN03,3H20, referred to above, the same group of workers, in continuation of their studies on hydrogen-bonding, has reported the crystal structure of HN03,H20 at both 85 K and 225 K. At each 

Stotskii, N. V. Bukhvalova, S. L. Gorbunova, and N. M. Stotskaya, Zhur. priklad. Khim., 

Densities of Aqueous Solutions of Miscellaneous Organic Compounds. 2-122 

2-184 List of Substances for Which Thermodynamic Property Tables Were Generated from NIST 

2-255 Thermodynamic Properties of R-22, Chlorodifluoromethane 2-340 Pressure-Enthalpy Diagram for Refrigerant 22 (Fig. 2-20). 2-342 

NH3 burners of a modern dual pressure plant for 0.40 Mt HNO3 per day. Courtesy of Uhde, Germany. 

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Catalytic gas-phase reactions play an important role in many bulk chemical processes, such as in the production of methanol, ammonia, sulfuric acid, and nitric acid. In most processes, the effective area of the catalyst is critically important. Since these reactions take place at surfaces through processes of adsorption and desorption, any alteration of surface area naturally causes a change in the rate of reaction. Industrial catalysts are usually supported on porous materials, since this results in a much larger active area per unit of reactor volume. 

The most widely used reactions are those of electrophilic substitution, and under controlled conditions a maximum of three substituting groups, e.g. -NO2 (in the 1,3,5 positions) can be introduced by a nitric acid/sul-phuric acid mixture. Hot cone, sulphuric acid gives sulphonalion whilst halogens and a Lewis acid catalyst allow, e.g., chlorination or brom-ination. Other methods are required for introducing fluorine and iodine atoms. Benzene undergoes the Friedel-Crafts reaction. ... 

Usually prepared by the action of NaCN on benzaldehyde in dilute alcohol. It is oxidized by nitric acid to benzil, and reduced by sodium amalgam to hydrobenzoin PhCHOHCHOHPh by tin amalgam and hydrochloric acid to des-oxybenzoin, PhCH2COPh and by zinc amalgam to stilbene PhCH = CHPh. It gives an oxime, phenylhydrazone and ethanoyl derivative. The a-oxime is used under the name cupron for the estimation of copper and molybdenum. 

Carius method The quantitative determination of S and halogens in covalent (organic) compounds by complete oxidation of the compound with cone, nitric acid and subsequent estimation of precipitated AgX or BaS04. 

CCls CHO. A colourless oily liquid with a pungent odour b.p. 98°C. Manut actured by the action of chlorine on ethanol it is also made by the chlorination of ethanal. When allowed to stand, it changes slowly to a white solid. Addition compounds are formed with water see chloral hydrate), ammonia, sodium hydrogen sulphite, alcohols, and some amines and amides. Oxidized by nitric acid to tri-chloroethanoic acid. Decomposed by alkalis to chloroform and a methanoate a convenient method of obtaining pure CHCI3. It is used for the manufacture of DDT. It is also used as a hypnotic. 

CgHgO, PhCH = CHCOiH. Colourless crystals. Decarboxylales on prolonged heating. Oxidized by nitric acid to benzoic acid. Ordinary cinnamic acid is the trans-isomer, m.p. 135-136 C on irradiation with u.v. light it can be isomerized to the less stable cis-isomer, m.p. 42" C. 

C3H6O4, HO OCHCOHj-CH OH. An un-crystallizable syrup it occurs in optically active forms. Prepared by oxidation of glycerin with nitric acid. 

Glycerol -dichlorohydrin, 2.3-dichloro-propanol, CH2CI CHC1 CH2 0H. Colourless liquid, b.p. 182 C. Prepared by the chlorination of propenyl alcohol. Oxidized by nitric acid to 1,2-dichloropropionic acid. Reacts with NaOH to give epichlorohydrin. 

C]2Hi50]2. Colourless needles m.pr. 286-288°C. When heated it decomposes into pyro mellitic anhydride, water and CO2. Occurs as the aluminium salt (honeystone) in some lignite beds. Prepared by oxidation of charcoal with concentrated nitric acid. 

C (rapid heating). Manufactured by the oxidation of lactose or the galactans from wood with nitric acid. When heated with water it forms a soluble lactone. Converted to furoic... 

Nitro-compounds are prepared by the direct action of nitric acid. The reaction is greatly facilitated if a mixture of nitric and sulphuric acid is used. 

Peroxonitrous acid, HOONO. Isomer of nitric acid (HNO2 plus H2O2). 

Ditrosonium hydrogen sulphate, chamber crystals, NOHSO4. White solid m.p. 73°C (decomp.). Prepared SO2 and fuming nitric acid. Used in diazotization. 

Crystallizes from water in large colourless prisms containing 2H2O. It is poisonous, causing paralysis of the nervous system m.p. 101 C (hydrate), 189°C (anhydrous), sublimes 157°C. It occurs as the free acid in beet leaves, and as potassium hydrogen oxalate in wood sorrel and rhubarb. Commercially, oxalic acid is made from sodium methanoate. This is obtained from anhydrous NaOH with CO at 150-200°C and 7-10 atm. At lower pressure sodium oxalate formed from the sodium salt the acid is readily liberated by sulphuric acid. Oxalic acid is also obtained as a by-product in the manufacture of citric acid and by the oxidation of carbohydrates with nitric acid in presence of V2O5. 

CgHgNa. While crystals m.p. 147 C, b.p. 267"C, darken rapidly in air. Prepared by reducing p-nitroaniline or aminoazobenzene. Oxidizing agents convert it to quinone derivatives, hence it cannot be diazotized with nitric acid. 

CfiHi 05 0 C6H4 CH20H. Colourless, bitter crystals, m.p. 20 PC soluble in water and alcohol, insoluble in chloroform. It occurs in the leaves, bark and twigs of species of willow and poplar. On oxidation with dilute nitric acid it is converted into helicin, the glucoside of salicylaldehyde, which has been made the starting point of further syntheses. Gives populin with benzoyl chloride. 

Strong oxidising acids, for example hot concentrated sulphuric acid and nitric acid, attack finely divided boron to give boric acid H3CO3. The metallic elements behave much as expected, the metal being oxidised whilst the acid is reduced. Bulk aluminium, however, is rendered passive by both dilute and concentrated nitric acid and no action occurs the passivity is due to the formation of an impervious oxide layer. Finely divided aluminium does dissolve slowly when heated in concentrated nitric acid. 

Dilute acids have no effect on any form of carbon, and diamond is resistant to attack by concentrated acids at room temperature, but is oxidised by both concentrated sulphuric and concentrated nitric acid at about 500 K, when an additional oxidising agent is present. Carbon dioxide is produced and the acids are reduced to gaseous oxides ... 

Amorphous carbon, having a far greater effective surface area than either diamond or graphite, is the most reactive form of carbon. It reacts with both hot concentrated sulphuric and hot concentrated nitric acids in the absence of additional oxidising agents but is not attacked by hydrochloric acid. 

Silicon, like carbon, is unaffected by dilute acids. Powdered silicon dissolves incompletely in concentrated nitric acid to give insoluble silicon dioxide, SiOj ... 

Concentrated nitric acid, however, is an oxidising agent and tin reacts to give hydrated tin(IV) oxide in a partly precipitated, partly colloidal form, together with a small amount of tin(II) nitrate, Sn(N03)2 ... 

Again, nitric acid readily dissolves lead but is unable to oxidise lead beyond the oxidation state -P 2. The reduction products of the nitric acid vary with the concentration of acid used, and a number of nitrogen oxides are usually obtained. Warm dilute nitric acid gives mainly nitrogen oxide, NO. 

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