White solids

A white solid, m.p. 178 C. Primarily of interest as a brominaling agent which will replace activated hydrogen atoms in benzylic or allylic positions, and also those on a carbon atom a to a carbonyl group. Activating influences can produce nuclear substitution in a benzene ring and certain heterocyclic compounds also used in the oxidation of secondary alcohols to ketones. 

HOCH2C = CCH2OH. White solid, m.p. 58 C, b.p. 238- C prepared by the high pressure reaction between ethyne and methanol and also from BrMgCCMgBr and methanal. Used in electroplating (Ni), as a corrosion inhibitor, and in paint and varnish removal. 

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. 

Chromium(IJ) chloride, chromous chloride, CrCl2- White solid (Cr plus HCl gas) dissolving to give a blue solution. Forms hydrates, widely used as a reducing agent. 

Copper I) chloride, CuCl. White solid (CuClj plus HCJ plus excess copper or SO2). Gives carbonyl and phosphine complexes. 

CgHftCljOa- A selective growth regulator herbicide for use against broad-leaved plants. White solid m.p. I38°C. 

A contact insecticide with the trade name Sevin . White solid, m.p. 142 C. It is prepared by reaction of I-naphthol with methyl isocyanate or with phosgene and a base. 

Dinilrogen pentoxide, N2O5. White solid (HNO3 plus P2OJ) readily decomposes to NO2 and O2, sublimes 32-5 "C. In solid slate (N02) (N03) gaseous molecules O2NONO2... 

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

NaOCHjCHa. White solid (Na in EtOH). Decomposed by water, gives ethers with alkyl halides reacts with esters. Used in organic syntheses particularly as a base to remove protons adjacent to carbonyl or sulphonyl groups to give resonance-stabilized anions. 

Thalliumilll) fluoride, TIF3 white solid (TI2O3 plus F2), immediately hydrolysed by water. 

Titanium IV) fluoride, TiF4. White solid (T1CI4 plus anhydrous HF). Forms [TiFJ- ion. 

CH3-[CHi]5.CH CH-[CH2]g-C02H. A white solid, m.p. 43-44°C, which is present in small quantities in animal fats and in milk. It is the only naturally occurring fatty acid with the trans configuration. 

Vanadium pentafiuoride, VF5, m.p. 19-5 C, b.p. 48°C. White solid immediately hydrolysed by water via VOF3 and VO2F. VF5 prepared V plus Fj. Forms hexafluorovanadates(V), MVFe, most easily in BrFj. 

The white solid oxides MjO and M 0 are formed by direct union of the elements. The oxides MjO and the oxides M"0 of calcium down to radium have ionic lattices and are all highly basic they react exothermically with water to give the hydroxides, with acids to give salts, and with carbon dioxide to give carbonates. For example... 

The larger cations of Group 1 (K, Rb, Cs) can be precipitated from aqueous solution as white solids by addition of the reagent sodium tetraphenylborate, NaB(C( H5)4. Sodium can be precipitated as the yellow sodium zinc uranium oxide ethanoate (sodium zinc uranyl acetate). NaZn(U02)3(CH3C00)y. 9H2O. by adding a clear solution of zinc uranyl acetate in dilute ethanoic acid to a solution of a sodium salt. 

In this case the covalency of boron is brought up to four because the donor molecule supplies the necessary electrons. The adduct formed, trimethylamine-borane, is a stable white solid. Other compounds of a similar kind are known, all derived from the simple structure H3N -> BH3. This compound is isoelectronic with ethane, i.e. it contains the same number of electrons and has the same shape. 

Aluminium oxide is a white solid, insoluble in water, with a very high melting point. If heated above red heat, it becomes insoluble in acids and alkalis, and can only be brought into solution by first fusing it with sodium or potassium hydroxide when an aluminate is formed. 

Pure anhydrous aluminium chloride is a white solid at room temperature. It is composed of double molecules in which a chlorine atom attached to one aluminium atom donates a pair of electrons to the neighbouring aluminium atom thus giving each aluminium the electronic configuration of a noble gas. By doing so each aluminium takes up an approximately tetrahedral arrangement (p. 41). It is not surprising that electron pair donors are able to split the dimer to form adducts, and ether, for example, forms the adduct. 

The trihalides closely resemble those of antimony. Bismuth(V) fluoride is known. It is a white solid, and a powerful oxidising agent. 

Sulphur trioxide can be collected as a white solid in a receiver surrounded by a freezing mixture of ice and salt. 

Tribromine octoxide, Br30g, is a white solid obtained when ozone and bromine react together at 273 K at low pressure. It is unstable above 200 K in the absence of ozone. It is known to exist in two forms, both soluble in water. 

There appears to be only one true oxide of iodine, diiodine pentoxide, IjOs- It is a white solid prepared by heating iodic acid(V) to 450 K ... 

This occurs naturally as a white solid in various crystalline forms, in all of which six oxygen atoms surround each titanium atom. Titanium dioxide is important as a white pigment, because it is nontoxic. chemically inert and highly opaque, and can be finely ground for paint purposes it is often prepared pure by dissolving the natural form in sulphuric acid, hydrolysing to the hydrated dioxide and heating the latter to make the anhydrous form. 

Chromium forms a white solid, hexacarhonyl, Cr(CO)j, with the chromium in formal oxidation state 0 the structure is octahedral, and if each CO molecule donates two electrons, the chromium attains the noble gas structure. Many complexes are known where one or more of the carbon monoxide ligands are replaced by other groups of ions, for example [CrfCOlsI] . 

Copperil) chloride, CuCl, is a white solid, insoluble in water. It is prepared as follows ... 

Zinc(II) oxide, ZnO, is prepared by heating the hydroxide ZnlOH) or the carbonate ZnCOj. It is a white solid, insoluble in water, but readily soluble in acids to give a solution containing the zincfll) cation, and in alkalis to give a hydroxozincate(II) anion ... 

The product, commonly called calomel, is a white solid, insoluble in water in its reactions (as expected) it shows a tendency to produce mercury(II) and mercury. Thus under the action of light, the substance darkens because mercury is formed addition of aqueous ammonia produces the substance HjN—Hg—Hg—Cl, but this also darkens on standing, giving HjN—Hg—Cl and a black deposit of mercury. 

Mercuryill) chloride is obtained in solution by dissolving mercury(II) oxide in hydrochloric acid the white solid is obtained as a sublimate by heating mercury(II) sulphate and solid sodium chloride ... 

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