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2228
<br />Chromic Nitrate
<br />when freshly prepd, giving blue or green sol"; becomes insc
<br />in acids on aging.
<br />Cr(OH)3.n1i201 shining, vitrous, jet-black particles. Use
<br />ful as catalyst in dehydrogenation of alcohols and paraffins
<br />hydrogenation of olefins.
<br />USE: As pigment; in tanning industry; as mordant; a
<br />catalyst for organic reactions,
<br />2228. Chromic Nitrate. CrN309; mol wt 238.03. C
<br />21.85%, N 17.65%, 0 60.50%. Cr(NO3)3, Prepn of anhyd
<br />salt from NZOS and Cr(CO),: Addison, Chapma, J. Chert
<br />Soc. 1964, 539; prepn of nonahydrate from Cr(01)and di
<br />HNO3 or by reducing CrO3 in the presence oft HNO3
<br />Chromium vol. 1, M. J. Udy, Ed., A.C.S. Monograph Series
<br />no. 132 (Reinhold, New York, 1956) pp 203-204.
<br />Pale green, extremely deliquesc powder. Non-volatile
<br />Dec above 60'. Sol in water, ethyl acetate, DMSO; practi
<br />cally insol in benzene, CC:14, CHC13: reacts with ether, some.
<br />times vigorously.
<br />Nonahydrate, deep violet, rhombic, monoclinic crystals
<br />mp about 60'; dec above 100'. Sol in water, alcohol. Aq
<br />soln slowly becomes green on heating and rapidly recovers
<br />the reddish -violet color on cooling. LDS6 in rats: 3.25 g/kg
<br />orally, Smyth et al., Am. Ind. Ilyg. Assoc. J. 30, 470 (1969).
<br />USE: Prepn of Cr catalyst; in textile printing; corrosion
<br />inhibitor.
<br />2229. Chromic Oxide. Anadonis green; chrome green;
<br />chrome ocher; chrome oxide green; chromic; chromium
<br />sesquioxide; green cinnabar; green oxide of chromium; green
<br />rouge; leaf green; oil green; ultramarine green; C.I. Pigment
<br />Green 17; C.I. 77288. Cr2O3: mol wt 1.42.02. Cr 68.43% 0
<br />31.57%. Prepd by reaction of sodium dichromate or chro-
<br />mate with sulfur: Copson in Chromium vol. 1, M. J. Udy,
<br />Ed., ACS Monograph Series no. 132 (Reinhold, New
<br />York, 1956) pp 277-278. Review: Wiesburg, paint Ind.
<br />Mag. 71(2), 11 (1956). See also Colour Index vol. 4 Ord ed.,
<br />1971) p 4662. Use as catalyst: R. Uma, J. C. Kuriacose,
<br />Indian Chem. Mfr. 8, 11 (1970). Cytotoxic effects: V. Bian-
<br />chi et al., Toxicology 17, 219 (1980),
<br />Light to dark green, fine, hexagonal crystals. mp about
<br />2435'. by about 3000', des 5.22. Turns brown ort heating
<br />but reverts to green color on cooling.Cryst Cr20, is ex-
<br />tremely hard; will scratch quartz, topnz, zircon. Practically
<br />insol in water, ale, ncclOne. Slightly sol in acids, alkalies.
<br />Caution: Trivalent chromiurn may cause skin irritation:
<br />S. Fregert, H. Rorsman, Arch. Derr". 90, 4 (1964).
<br />USE: In abrasives, refractory materials, electric semicon.
<br />ductors; as pigment, particularly in coloring glass; in alloys;
<br />printing fabrics and banknotes; as catalyst for organic and
<br />inorganic reactions.
<br />2230. Chromic Phosphate. CrO,P; mol wt 146.99. Cr
<br />35.387., O 43.54%, P 21.07%. CrPO4. Prepn: Ness et al., J.
<br />Am. Chem. Soc. 74, 4685 (1952); Eickhoff, Kebrich, U.S.
<br />pat. 2,749,214 (1956 to National Lead); Wegenknecht, Ger.
<br />pats. 1,046,597 (1958); 1,056,104 (1959).
<br />Gray -brown to black crystals of amorphous solid. Does
<br />not melt by 1800'. d32.5 2.94. Partially oxidizes to CrO3 on
<br />heating in air. Practically insol in water, acetic acid, HCI,
<br />aqua regia.
<br />Hemiheptahydrate, Arnaudon's green, Plessy's green.
<br />Blue-green powder. d 2.15. Practically insol in water; sol in
<br />acids.
<br />Hexahydrate, violet crystals. Loses water gradually on
<br />heating, becoming anhydr after one hour at 800' or 3-4 firs
<br />at 500'. d14 2.121. Practically insol in water; slightly sol in
<br />acetic acid solns; readily sol in mineral acids, alkalis, oxalic
<br />acid solns.
<br />Radioactive form, CrJ2PO4, Plimphocol.
<br />USE: Green pigment; in wash primers; in catalysts for de-
<br />hydrogenation of hydrocarbons or polymerization of olefins.
<br />THERAP CAT: Cr32PO4 as radioactive agent.
<br />2231 Vhrnmfe P.# ... I.— n. r a ... .
<br />book of Preparative inorganic Chemistry vol. 2, Ci. Brauer,
<br />Ed. (Academic Press, New York, 2nd ed., 1965) p 1372.
<br />Trihydrate, potassium trioxolatotriaquochrornate(III).
<br />Black -green, monoclinic scales with transparent blue edges.
<br />Freely sol in water; practically insol in alcohol.
<br />USE: In tanning industry; dyeing chromate colors on wool.
<br />2232. Chromic Potassium Sulfate. Potassium chromic
<br />sulfate; potassium disulfatochrornate(Ill). CrKO8S2; mol wt
<br />283.23. Cr 18.36%. K 13.81%, 0 45.19%, S 22.64%. KCr-
<br />(SO,)2. Dodecahydrate produced by reduction of K2Cr20r
<br />with SO2: Copson in Chromium vol, 1, M. J. Udy, Ed.,
<br />A.C.S. Monograph Series no. 132 (Reinhold, New York,
<br />1956) p 281; electrolytic tnanuL• Nishihara et ol, Japan. pat.
<br />2164('60), C.A. 55, 5200e (1961).
<br />Dodecahydrate, chronic alum, K1Cr(S06H4)2(llZO .-
<br />61120: Duval. Chint. Anal. (Paris) 44, 102 (1962), C.A. 57,
<br />9479d (1962). Large, violet -red to black, octahedral, cubic
<br />crystals; ruby -red under transmitted light. d23 1.83. nip 89';
<br />at 400° loses all its H2O. Sol in 4 parts cold, 2 parts boiling
<br />water; practically insol in alcohol. The aq sola is violet
<br />when cold, green when hot. The violet color returns after a
<br />few weeks at room temp.
<br />USF: Mordant for dyeing fabrics uniformly; tanning leath-
<br />er; printing calico; rendering glue and guru insol; manuf ink,
<br />other chromium salts; waterproofing fabrics; hardening
<br />photographic emulsions.
<br />2233. Chromic Sulfate. Cr20tjS3; mol wt 392.20. Cr
<br />26.52%, O 48.95% S 24.52%. Cr2(SO4),. Prepn of anhydr
<br />salt by dehydration of hydrated forms: Rollinson, Bailar,
<br />Jr., Inorg. Syn. 2, 197 (1946).
<br />Peach -colored solid. d 3.012. Practically insol in water
<br />and acids. MLD i.v. in mice: 247 mg/kg, Handbook of
<br />Toxicology vol. 1, W. S. Spector, Ed. (Saunders, Philadel-
<br />phia, 1956) pp 70-71.
<br />Hydrates are known in both green and violet modifica-
<br />tions, and have several degrees of hydration up to 181120:
<br />Lukaszewski, Redfern, Nature 190, 805 (1961); Udy in
<br />Chromium vol. 1, M. J. Udy, Ed., A.C.S. Monograph Series
<br />no. 132 (Reinhold, New York, 1956) pp 213-217, 288. The
<br />technical product comes in the form of a finely granular,
<br />dark -green flake or powder approximating the formula
<br />Cr2(SO,),.10H2O. Readily sol in water; almost insol in ale.
<br />Itasic chronric.strtfarex oft
<br />he lypc Cr(OII)SO4.n1120 lire of
<br />importance in the tanning industry: Udy, hoc. cit. and Pp
<br />278-280, 305-308. Technical grades are available in two
<br />degrees of basicity, one-third and one-half, as finely granu-
<br />lar dark -green Bakes or powder contg about 25% 0202.
<br />Readily sol in water.
<br />USE: Insolubilization of gelatin; in catalyst preps; as mor-
<br />dant in textile industry; in tanning of leather; in chrome
<br />plating; in manuf of Cr, CrO3, and Cr alloys; to improve
<br />lispersibility of vinyl polymers in water; in manuf of green
<br />varnishes, paints, inks, glazes for porcelain.
<br />2234. Chromium. Cr, at, wt 51.996; at. no. 24; valences
<br />1-6. Four naturally occurring isotopes: 50 (4.357.); 52
<br />83.79%); 53 (9.507.); 54 (2.36%); artificial radioactive iso-
<br />opes: 46-49; 51; 55; 56; longest -lived isotope is "Cr (Ty
<br />M8 days) prepd by (n,y) reaction from soCr. Reported
<br />rbundance in earth's crust varies from 100 to 300 ppm.
<br />discovered by 1797 by Vauquelin. Obtained from chrome
<br />rre, chromite (FeCr204), by a silicothermic or aluminother-
<br />nic process. Reviews of chromium, its alloys and compds:
<br />:hromium, M. J. Udy, Ed., A.C.S. Monograph Series, no.
<br />32 (Reinhold, New York, 1956) vol. 1, 433 pp; vol. 2,402
<br />op; Rollinson, "Chromium, Molybdenum and Tungsten" in
<br />:omprehensive Inorganic Chemistry vol. 3, J. C. Bailar, Jr. et
<br />d. Eds. (Pergamon Press, Oxford, 1973) pp 623-700; J. H.
<br />Vestbrook in Kirk -Othmer Encyclopedia of Chemical Tech-
<br />ology vol. 6 (Wiley -Interscience, New York, 3rd ed., 1979)
<br />,p 54-82. Important trace element. Review of biological
<br />unction of the chromium(III) ion: Mertz, Physiol Rev 49,
<br />high g polish. d 7.14. mp 1960°. I
<br />(251: 5.5R cal/9-atom deg. Laten
<br />3.5 kcal/g-atom; latent heat of va
<br />kcal/g-atom. Reacts with dil IIC1,
<br />attacked by caustic alkalies and afk
<br />dized by air, even in presence of nil
<br />Caution: Chromic acid or chroma
<br />trial hnznrds. Irritant effects on t
<br />passages lead to ulceration. Oral it
<br />vere irritation of the gastrointestinal
<br />and renal damage. Chromium(Ill)
<br />or no toxicity. This substance and
<br />pounds have been listed as know
<br />Annual Report on Carcinogens (NT
<br />USE: In manuf of chrome -steel or
<br />loys (stainless steel); for greatly in
<br />durability of metals; for chromeplatii
<br />man-made "Cr isotope as tracer in
<br />and in the determination of od vo
<br />as Na chromate).
<br />2235, Chromium Carbo Cit
<br />C6Cr0¢¢: mol wt 220.07. C 32.75%,
<br />Cr(CO)6. Prepn from Cr salts and (
<br />Grignard reagent: Owen et al.. InarR
<br />the presence of Mg and ether: Wend
<br />(1961 to Diamond Alkali); in the p
<br />glyme: Podall et al., J. Am. Chert. c
<br />the presence of Na and an aromatic
<br />Wyman, U.S. pat. 3,053,629 (1962 to
<br />presence of 12 and a nitrile: Wotiz, U,
<br />to Diamond Alkali).
<br />Orthorhombic, highly refractive c
<br />room temp. Sinters at 90'; dec at 1
<br />Burns with a luminous flame. drs
<br />(mm): 0.04 (0'); 1.0 (481; 66.5 (100°).
<br />ter, ethanol, methanol; sol in ether,
<br />solvents. Solis or impure solid dec b
<br />100 mg/kg i.v., Strohmeier, Z. Naturfr
<br />USE: in catalysts for olefin polymeri
<br />tion; gasoline additive to increase oct:
<br />chromous oxide, CrO.
<br />2236. Chromium Dinxide. Cr(:),;
<br />61.90%, O 38.10%. Prepn: Wiihler,
<br />Tharner et al.. .1. Ant. Chert. Soc. 79, 5,
<br />al., J. Appl Phvs. 32, Sir
<br />ppl. 37�
<br />thur, Ingraham, U.S, pats. 55;
<br />both to du Pont). Reviews: Wd, Pa;
<br />(1972); Rollinson in Comprehensive Im
<br />3, J. C. Bailar, Jr. et al., Fds. (Perg:
<br />1973) pp 689-690.
<br />Black, ferromagnetic crystals; rutile
<br />Metastable in air; various temperatures
<br />for decompn to Cr203.
<br />USF: in magnetic recording tapes; as
<br />2237. Chromium Tetrafhtoride. Ca
<br />Cr 40.63%, F 59.37%. Prepd by reacti
<br />CTC13: von Wartenberg, Z. Anorg. Allg
<br />(1941); Clark, Sadana, Can. J. Chem. 4_
<br />Very dark greenish -black, amorphous
<br />to moist air becomes brown on surfacr
<br />MP (estimated) 277': Fergusson in Hal
<br />3, V. Gutmann, Ed. (Academic Press,
<br />242. by about 400' evolving steel -blue
<br />vacuo above 100'; d 2.89. Less reactive
<br />;readily form Werner complexes; does n
<br />SO2, S03, pyridine. Sol in water with rar,
<br />tically insol in most organic solvents. C
<br />nitely in vacuo in well dried Pyrex or sil
<br />Caution: A strong irritant.
<br />2238, Chromium Trioxide. Chromic
<br />hydride. CrO3; mol wt 100 01 Cr 57 on
<br />
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