Solution alkaline

Dissolves in alkaline solutions to give purple-red solutions which are precipitated as lakes by heavy metal salts. Occurs naturally as a glucoside in madder but produced synthetically by fusing anthraquinone-2-sulphonic acid with NaOH and some KCIO3. Applied to the mordanted fibre. Al(OH)3 gives a bright red lake, Cr(OH)3 a red lake, FefOH) ... 

M.p. 190-192 C. The enolic form of 3-oxo-L-gulofuranolactone. It can be prepared by synthesis from glucose, or extracted from plant sources such as rose hips, blackcurrants or citrus fruits. Easily oxidized. It is essential for the formation of collagen and intercellular material, bone and teeth, and for the healing of wounds. It is used in the treatment of scurvy. Man is one of the few mammals unable to manufacture ascorbic acid in his liver. Used as a photographic developing agent in alkaline solution. 

Isobutyric acid, dimethylacetic acid, 2-methylpropanoic acid, (CHjjjCH COOH, colourless syrupy liquid with an unpleasant odour b.p. 154°C. Prepared by oxidation of 2-methylpropanol with K2Cr207 and H2SO4. Salts soluble in water. Used in alkaline solution for sweetening gasoline. 

Addition of acid will reduce the concentration of ", whilst in alkaline solution the concentration of will increase. Since, in order for precipitation to occur, the solubility product of the sulphide must be exceeded, i.e. 

Fieser s solution An aqueous alkaline solution of sodium anthraquinone -sulphonale (silver salt) reduced with sodium dithionite, Na2S204, and used as a scrubbing solution for partially removing O2 from, e.g., N2. 

C12H9N3O4. A brownish-red powder, soluble in sodium hydroxide. Used for the detection and estimation of magnesium, with which it forms a blue lake in alkaline solutions. 

Colourless prisms m.p. 130 C. Manufactured by treating maleic anhydride with water. It is converted to the anhydride by heating at By prolonged heating at 150 "C or by heating with water under pressure at 200 C, it is converted to the isomeric (trans) fumaric acid. Reduced by hydrogen to succinic acid. Oxidized by alkaline solutions of potassium permanganate to mesotartaric acid. When heated with solutions of sodium hydroxide at 100 C, sodium( )-malate is formed. Used in the preparation of ( )-malic acid and in some polymer formulations. 

Nessler s reagent An alkaline solution of Hglj in KI used for detecting and estimating ammonia (brown colour or precipitate formed). 

The normal form in which nickel is weighed in analysis. There is metal-metal bonding in the solid. The red complex is precipitated from alkaline solution. 

The UV-visible absorption spectrum of Ru(2,2 -bipyridine)3 maximum at about 450 nm, from which the energy in volts for process XI-39 may be estimated. The standard reduction potential for the R" /R couple is about 1.26 V at 25°C. Estimate from this information (and standard reduction potentials) the potential in volts for processes XI-40 and XI-41. Repeat the calculation for alkaline solutions. 

As a furtlier example for tire meaning of ex situ investigations of emersed electrodes witli surface analytical teclmiques, results obtained for tire double layer on poly crystalline silver in alkaline solutions are presented in figure C2.10.3. This system is of scientific interest, since tliin silver oxide overlayers (tliickness up to about 5 nm) are fonned for sufficiently anodic potentials, which implies tliat tire adsorjDtion of anions, cations and water can be studied on tire clean metal as well as on an oxide covered surface [55, 56]. For tire latter situation, a changed... 

Alonso C, Salvarezza R C, Vara J M and Arvia A J 1990 The meohanism of silver (I) oxide formation on polyorystalline silver in alkaline solution. Determination of nuoleation and growth rates Electrochim. Acta 35 489-96... 

Modestov A D, Zhou G-D, Ge FI-FI and Loo B FI 1995 A study by voltammetry and the photocurrent response method of copper electrode behavior in acidic and alkaline solutions containing chloride ions J. Electroanal. Chem. 380 63-8... 

Lutzenkirchen-Flecht D and Strehblow FI-FI 1998 Bromide adsorption on silver in alkaline solution A surface analytical study Ber. Bunsenges. Phys. Chem. 102 826-32... 

The following redox potentials are given for the oxidation of manganese(II) to manganese(III) in acid and alkaline solution. 

Note that dinitrogen oxide is the other product. In alkaline solution, however, hydroxylamine oxidises iron(II) hydroxide to iron(III) hydroxide and is itself reduced to ammonia. This is an example of the effect of pH change on oxidation-reduction behaviour (p. 101). ... 

With a nitrate in alkaline solution, ammonia is evolved quantitatively by Devarda s alloy (Al, 45% Cu, 50% and Zn, 5%). This reaction can be used to estimate nitrate in absence of ammonium ions (see below) ... 

By the evolution of ammonia with Devarda s alloy in alkaline solution in absence of ammonium ions this is used quantitatively, the ammonia being absorbed in excess standard acid and the excess acid back-titrated. 

Hydrogen sulphide is a reducing agent in both add and alkaline solution as shown by the following examples ... 

These are practically insoluble in water, are not hydrolysed and so may be prepared by addition of a sufficient concentration of sulphide ion to exceed the solubility product of the particular sulphide. Some sulphides, for example those of lead(II), copper(II) and silver(I), have low solubility products and are precipitated by the small concentration of sulphide ions produced by passing hydrogen sulphide through an acid solution of the metal salts others for example those of zincfll), iron(II), nickel(II) and cobalt(II) are only precipitated when sulphide ions are available in reasonable concentrations, as they are when hydrogen sulphide is passed into an alkaline solution. 

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