Monoclinic prisms

Oxalic Acid Dihydrate. OxaUc acid dihydrate is made up of odorless, colorless, monoclinic prisms or granules which contain 71.42 wt % anhydrous oxaUc acid and 28.58 wt % water. 

Crystalline Structures. Crystal shape of amino acids varies widely, for example, monoclinic prisms in glycine and orthorhombic needles in L-alanine. X-ray crystallographic analyses of 23 amino acids have been described (31). L-Glutamic acid crystallizes in two polymorphic forms (a and P) (32), and the a-form is mote facdely handled in industrial processes. The crystal stmeture has been determined (33) and is shown in Figure 1. 

Hydroxyacetanilide. This derivative (21), also known as 4-acetamidophenol, acetaminophen, or paracetamol, forms large white monoclinic prisms from water. The compound is odorless and has a bitter taste. 4-Hydroxyacetani1 ide is insoluble in petroleum ether, pentane, and ben2ene slightly soluble in diethyl ether and cold water and soluble in hot water, alcohols, dimethylformamide, 1,2-dichloroethane, acetone, and ethyl acetate. The dissociation constant, pfC, is 9.5 (25°C). 

The acid occurs both as colorless triclinic prisms (a-form) and as monoclinic prisms ( 3-form) (8). The P-form is triboluminescent and is stable up to 137°C the a-form is stable above this temperature. Both forms dissolve in water, alcohol, diethyl ether, glacial acetic acid, anhydrous glycerol, acetone, and various aqueous mixtures of the last two solvents. Succinic acid sublimes with partial dehydration to the anhydride when heated near its melting point. 

The deterrnination of the stmcture of Fe (00) 2 proved to be a difficult problem. An early report on the crystal stmcture claimed the molecule was a monoclinic prism and estabHshed the molecular formula (22). In a later report stmcture (8) was shown to be a triangular array of iron atoms with two bridging and 10 terminal CO molecules. This accepted stmcture was initially deduced from an x-ray crystal stmcture of the Fe2(CO)22H analogue (23). 

Properties. Dicyandiamide (2) (cyanoguanidine [461-58-5]) is the dimer of cyanamide and crystallizes ia colorless monoclinic prisms. It is amphoteric, and generally soluble in polar solvents and insoluble in nonpolar solvents. Its properties are Hsted in Table 3. 

Z-Ecgonine, CgHigOgN. HjO. This substance was first obtained I Lossen as the final basic hydrolytic product of the action of acids c cocaine, and is obtainable in like manner from several of the alkaloii occurring with cocaine (see above). It crystallises from dry alcohol i monoclinic prisms, m.p. 198° (dec.), 205° (dry), [a]n — 45-4°, is soluble i water, sparingly so in alcohol, insoluble in most organic liquid Eegonine forms Salts with bases and acids the hydrochloride crystallis... 

B. HCl. H2O, m.p. 242° (dry), [ajo — 117-6° (dry salt, c — 1-214, H2O), forms monoclinic double pyramids, or silky prisms with 2H2O, from its saturated aqueous solution. The dry salt is moderately soluble in water (1 in 38-5 at 10°), or ether (1 in 325 at 10°), readily in chloroform. The acid hydrochloride, B. 2HC1. HjO, forms large monoclinic prisms easily soluble in water or alcohol. The dihydrobromide, B. 2HBr. 2H2O, crystallises well from water and has — 114-3° (dry salt, c = M/40, H2O). The... 

Brucine crystallises from water or aqueous alcohol in monoclinic prisms containing 4H2O, m.p. 105° or 178° dry), [a]n — 119° to — 127° (CHCI3) or — 80-1° (EtOH). The alkaloid is slightly soluble in cold water fl in 320), more so in boiling water (1 in 150), very soluble in alcohol, chloroform, or amyl alcohol, sparingly soluble in ether (1 in 134). 

Metafor 3- Mononitrophenol Monoclinic prisms from eth or dil HC1 mp 97° bp 194° at 70mm, decomps when distd at ordinary pressure d 1.485g/cc at 20°, 1.2797 at 100°. Does not volatilize with steam cannot be prepd by the nitration of phenol. Can be obtained by boiling diazotized m-nitroaniline with w and sulfuric acid (Ref 3). SI sol in w, sol in ale. Highly toxic by ingestion and inhalation Refs 1) Beil 6, 222-24, (116), [212-14]... 

Crystalline form. .. mn. pr. monoclinic prisms. Here, mn is a variant of the mcl abbreviation used in the CRC. Don t let these small differences throw you. A secret is that all handbooks have a listing of abbreviations at the front of the tables. Shhhh Don t tell anyone. It s a secret. 

Brownish to white monoclinic prisms, crystalline solid or powder with a phosgene-like odor (technical grade). An odor threshold concentration of 88 pg/kg was reported by Sigworth (1964). 

Colorless solid (tetracene impurities impart a yellow color) or monoclinic prisms crystallized from alcohol. Solutions have a slight blue fluorescence. 

Physical Form. Colorless, monoclinic prisms, crystals commercial crystals are yellow... 

Pale-green monoclinic prisms unstable readily oxidized on exposure to air decomposes on heating very soluble in water also soluble in alcohol and ether. 

Hydroxybenzoic acid is obtained as white crystals, fine needles, or fluffy white crystalline powder. It is stable in air and may discolor gradually in sunlight. The synthetic form is white and odorless. When prepared from natural methyl salicylate, it may have a light yellow or pink tint and a faint, wintergreen-like odor. w-Hydroxybenzoic acid crystallizes from water in the form of white needles and from alcohol as platelets or rhombic prisms. -Hydroxybenzoic acid crystallizes in the form of monoclinic prisms. Various physical properties of hydroxybenzoic acids are listed in Tables 1—4. 

Etbyl-3-nitrobenzoate, monoclinic prisms, mp 47°, bp 296° It may be prepd by saturating an ale soln of the acid with. HCl gas from the acid salt of 3 nitrobenziminoethylether from the 3-nitro acid and diazoethane and from the >nitro benz in bulling abs ale and HCl gas Ref Beil 9, 378, (151), (154) [248] Etbyl 4-nitrobenzoate, pi tits (from ale), mp 57°. It may.be prepd from the acid in ale in the presence of HCl, from the methyl ester and excess ale in the presence of KOCH3 Ref Beil 9, 390 [258]... 

Tetraquo-diammino-chromic Chloride, [Cr(NH8)2(H2Q)4]Cl3, is prepared in the same manner as the bromide by decomposing the basic salt. It forms light red monoclinic prisms which are very soluble in water, insoluble in alcohol, and on warming the aqueous solution with a little acid is transformed into the dichloro-diaquo-salt. 

Manganous thiocyanate forms two compounds with pyridine, dipyridino-manganous thiocyanate, [Mn(CsH5N)2](SCN)2, which is yellow, and tetrapyridino-manganous thiocyanate, [Mn(C8H6N)4](SCN)2, a colourless substance crystallising in monoclinic prisms. The tetra-derivative is unstable in air.8... 

A basic copper chlorate is formed when soln. of potassium chlorate acidified with sulphuric acid are electrolyzed with an alternating current between copper electrodes (L. Rossi) 83 when the hydrate is heated above 100° (A. Wachter) when a soln. of copper chlorate be mixed with pieces of marble or urea, and heated in a sealed tube to 130° (L. Bourgeois) when the hydroxides of the alkalies or alkaline earths act on cupric chlorate soln., or copper hydroxide acts on soln. of potassium chlorate (A. Brochet) when hydrated cupric oxide or cupric hydroxide acts on cupric chlorate soln. (P. Sabatier) or when potassium chlorate acts on cupric acetate soln. (A. Casselmann), basic cupric chlorate is obtained. The basic chlorate forms bluish-green monoclinic prisms of sp. gr. 3 55 and composition 4Cu0.C1205.3H20, that is, Cu(C103)2.3Cu(0H)2, which A. Werner considers to be hexahydroxyl cupric chlorate ... 

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