A Comprehensive Treatise on Inorganic and Theoretical Chemistry: volume 14. Fe (Part III), Co

900 Pages·34.92 MB·English

by  Mellor J.W.

A COMPREHENSIVE TREATISE ON INORGANIC AND
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VOLUME XIV
Fe (Part III), Co
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A COMPREHENSIVE TREATISE
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INORGANIC AND THEORETICAL
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BY
J. W. MELLOR, D.Sc, F.R.S.
VOLUME XIV
WITH 277 DIAGRAMS
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CONTENTS
CHAPTER LXVI (continued)
IRON (continued)
§ 35. The Iron Fluorides (1) ; § 36. The Iron Chlorides—Ferrous Chloride (9) ; § 37. The
Iron Chlorides—Ferric and Ferrosic Chlorides (40) ; § 38. The Iron Bromides (117) ;
§ 39. The Iron Iodides (127) ; § 40. The Iron Sulphides—Ferrous Sulphide and
Pyrrhotite (136) ; § 41. Ferric Sulphide (179) ; § 42. The Iron Sulphides—Iron
Disulphide (199) ; § 43. Ferrous Sulphate (242) ; § 44. The Complex Salts of Ferrous
Sulphate (288) ; § 45. Ferric Sulphate (302) ; § 46. The Basic Ferric Sulphates (328) ;
§ 47. Complex Salts with Ferric Sulphate (336) ; § 48. The Iron Carbonates (355) ;
§ 49. The Iron Nitrates (375) ; § 50. The Ferrous Phosphates (390) ; § 51. The
Ferric Phosphates (401).
CHAPTER LXVII
COBALT
§ 1. The History of Cobalt (419) ; § 2. The Occurrence of Cobalt (422) ; § 3. The
Extraction of Cobalt (433) ; § 4. The Separation of Cobalt and Nickel (440) ;
§ 5. The Preparation of Metallic Cobalt (446) ; § 6. The Physical Properties of
Cobalt (457) ; § 7. The Chemical Properties of Cobalt (507) ; § 8. The Atomic
Weight and Valency of Cobalt (525) ; § 9. Intermetallic Compounds or Alloys of
Cobalt (529) ; § 10. Cobalt Suboxide and Monoxide (558) ; § 11. Cobaltosic Oxide
and Intermediate Oxides (577) ; § 12. Cobaltic Oxide and its Hydrates (584) ;
§ 13. The Higher Oxides of Cobalt—Cobalt Dioxide (598) ; § 14. Cobalt Fluorides
(603); § 15. Cobaltous Chloride (611); § 16. Cobaltic Chloride and its Complex
Salts (653) ; § 17. The Cobaltic Ammines (688) ; § 18. Cobaltous Bromide (711) ;
§ 19. Cobaltic Bromide, and its Complex Salts (720) ; § 20. Cobaltous Iodide (737) ;
§ 21. Cobaltic Iodide and its Complex Salts (742); § 22. Cobalt Sulphides (750) ;
§ 23. Cobaltous Sulphate (761) ; § 24. Cobaltic Sulphate and its Complex Salts
(787) ; § 25. Cobaltous Carbonate (808) ; § 26. Cobaltic Carbonate and its Complex
Salts (813) ; § 27. Cobaltous Nitrates (821) ; § 28. Cobaltic Nitrate and its Complex
Salts (830) ; § 29. Cobaltous Phosphates (851) ; § 30. Cobaltic Phosphates (856).
INDBJX . . . . . . . . . . . . .. 861
V

ABBREVIATIONS
aq. — aqueous
atm. «•• atmospheric or atraosphcre(s)
at. vol. = atomic volume(s)
at. wt. = atomic weight(s)
T° or 0K » absolute degrees of temperature
b.p. •• boiling point(s)
0° a" centigrade degrees of temperature
eoeff. «= coefficient
cone. "•« concentrated or concentration
dil. — dilute
eq. =* equivalent(s)
f.p. «•= freezing point(s)
m.p. «» melting point(s)
mol(s) -. /^am-molecule(s) .
v ' \gram-molecular
mol. ht. s=s molecular heat(s)
mol. vol. « molecular volume(s)
mol. wt. «=» molecular weight(s)
press. •— pressure(s)
sat. ss saturated
BoIn. •= solution(s) •
sp. gr. »BI specific gravity (gravities)
sp. ht. * specific heat(s)
sp. vol. —* specific volume(s)
temp. •» temperature(s)
vap. = vapour
In the CFOSS references the first number in clarendon type is the number of the
volume; the second number refers to the chapter; and the succeeding number refers to the
" §," section. Thus 5. 88, 24 refers to § 24, chapter 88, volume 5.
The oxides, hydrides, halides, sulphides, sulphates, carbonates, nitrates, and phosphates
are considered with the basic elements ; the other compounds are taken in connection with
the aoidio element. The double or complex salts in connection with a given element include
those associated with elements previously discussed. The carbides, silicides, titanides,
phosphides, arsenides, etc., are considered in connection with carbon, silicon, titauium, etc.
The intermetallio compounds of a given element include those associated with elements
previously considered.
The use of triangular diagrams *or representing the properties of three-component
systems was suggested by Gt, Or. Stokes {JProc. Boy. Soc., 49. 174, 1891). The method was
immediately taken up in many directions and it has proved of great value. With practice it
becomes as useful for representing the properties of ternary mixtures as squared paper is for
binary mixtures. The principle of triangular diagrams is based on the fact that in an equi
lateral triangle the sum of the perpendicular distances of any point from the three sides is
a constant. Qiven any three substances A, JB, and C, the composition of any possible
combination of these can be represented by a point iu or on the triangle. The apices of the
vii
viii ABBREVIATIONS
triangle represent the single components A, B, and O, the sides of the triangle represent binary
mixtures of A and B B and C or C and A ; and points within the triangle, ternary mixtures.
1 1
The compositions of the mixtures can be represented in percentages, or referred to unity, 10,
etc. In Fig. 1, pure A will be represented by a point at the apex marked A. If 1OO be the
Fia. 1.
standard of reference, the point A represents 100 per cent, of A and nothing else; mixtures
containing 80 per cent, of A are represented by a point on the line 88, 6O per cent, of A by a
point on the line 66, etc. Similarly with B and C—Figs. 3 and 2 respectively. Combine
Figs. 1, 2, and S into one diagram by superposition, and Fig. 4 results. Any point in this
/OO 3O 6O <90 2O OVoOf B
FIG. 4.—Standard Reference. Triangle.
diagram, Fig. 4, thus represents a ternary mixture. For instance, the point M represents a
mixture containing 20 per cent, of A 2O per cent, of B and 6O per cent, of O-
t %
CHAPTER LXVI {continued)
IRON {continued)
§ 35. The Iron Fluorides
IN 1771, C. W. Scheele x dissolved iron in hydrofluoric acid but he did not obtain
well-defined crystals from the soln., owing to impurities which were introduced by
the action of the acid on the glass containing vessel. H. Moissan, and O. Ruff
and E. Ascher observed the conditions under which fluorine attacks iron, and the
iron oxides. C. Poulenc found that when iron, or anhydrous ferrous chloride is
heated to redness in a current of dry hydrogen fluoride, colourless, monoclinic
crystals of ferrous fluoride, FeF , are formed. The anhydrous salt was also
2
obtained by J. J. Berzelius, and A. Scheurer-Kestner, by heating the hydrated
salt out of contact with air, or better, in a current of dry hydrogen fluoride. The
product obtained by A. Ferrari by heating the hydrated salt in hydrogen did not
appear crystalline when examined by the X-radiogram process, but after heating
the residue with ammonium fluoride in hydrogen, crystals were developed.
Ii. Hackspill and R. Grandadam obtained it by heating iron with sodium fluoride :
Fe+2NaF-= FeF -f-2Na ; and O. Ruff and E. Ascher, by heating ferric fluoride
2
above 400°, or by reducing it with iron, ammonia, sulphur dioxide, or hydrogen.
A. Scheurer-Kestner obtained green, prismatic crystals of the octohydrcde,
FeF .8H O, by evaporating for some days the green soln. obtained by dissolving
2 2
iron in hydrofluoric acid of sp. gr. 1-07. J. Li. Gay Lussac and L*. J. Thenard, and
J. J. Berzelius, under similar conditions, obtained the tetrahydrate, FeF .4H O ;
2 2
and C Poulenc showed that the tetrahydrate is formed when the soln. containing
only a little acid, is evaporated at ordinary temp. W. Biltz and E. Rahlfs observed
that the addition of alcohol to the aq. soln. precipitates the tetrahydrate.
O. Ruff and E. Ascher said that the anhydrous salt is white. A. Scheurer-
Kestner described the crystals of the anhydrous salt as small, yellow, quadratic
prisms ; and C. Poulenc, as transparent, lustrous, branching, monoclinic prisms.
C. Poulenc observed that the tetrahydrate forms white, rhombohedral crystals.
According to V. M. Goldschmidt, the X-radiograms show that the crystals of the
anhydrous salt are tetragonal of the rutile type, like those of the anhydrous
fluorides of magnesium, zinc, manganese, cobalt and nickel. The lattice dimensions
are «=3*83 A., and c—3-36, so that a : c —1 : 0*69 ; and the distance between the
iron and fluorine atoms is about 2-11 A. A. Ferrari gave a=4-670 A., c=3-297,
and a : c—1 : 0*706. O. Poulenc gave 4*09 for the sp. gr. of the anhydrous salt ;
and W. Biltz and E. Rahlfs, 4-09 at 25°/4°. A. Ferrari calculated 4-333 from the
lattice constants, and O. Ruff and E. Ascher, 3-95. O. Ruff and E. Ascher gave
22-9 for the mol. vol. ; and V. M. Goldschmidt, and J. W. Griiner calculated values
for the atomic radius of anion and cation. W. Biltz and E. Rahlfs gave 2-095 at
20°/4° for the sp. gr. of the tetrahydrate, and 79-19 for the mol. vol.
C. Poulenc said that the anhydrous salt volatilizes at 1100°. K. Jellinek and
A. Rudat noted that the salt is solid at 700° ; and W. Biltz and E. Rahlfs estimated
that the m.p. exceeds 1000°. A. Ferrari discussed the relation between the m.p.
and the space-lattice. For the dehydration of the hydrate, vide supra. K. Jellinek
and A. Rudat gave the vap. press., p, of the fluorine at 773° K., 873° K., and 973° K.,
P=—log 40-05, —log 35-14, and —log 31*06 respectively ; and they calculated the
heat of formation to be (Fe,F )=154-2 CaIs. ; O. Ruff and E. Ascher, and H. von
2
VOL. XIV. B
2 INORGANIC AND THEORETICAL CHEMISTRY
Wartenberg gave (Fe,F ,Aq.) = 177-2 CaIs. ; E. Petersen gave 2AgF-Aq.+FeCl .Aq.
2 2
=2AgCl+FeF .Aq.+31-8 CaIs., or Fe(OH) +2HF.Aq.=FeF .Aq.+26-6 Cais. ;
2 2 2
and M. Rerthelot gave (Fe,F ,Aq.)=-127 CaIs. G. Beck discussed the free energy
2
of the salt. R. Peters observed that ferrous fluoride in aq. soln. is probably as
strongly ionized as is ferrous chloride since the electrical conductivity of a mixed
soln. of ferrous chloride and sodium fluoride does not deviate much from the value
calculated from the mixture rule ; and similarly also for the lowering of the f.p.
of these soln.
C. Poulenc observed that at a dull red-heat, ferrous fluoride is partially reduced
by hydrogen* and at a higher temp, the reduction is complete. K. Jellinek and
A. Rudat found the equilibrium values for the reaction : FeF +H ^2HF+Fe,
2 2
log (P2HFAPU) for 500°, 600°, and 700° are respectively —2-78, —2-02, and —1-23.
3
For the direct reduction, and the reverse reaction, with p vol. per cent, of hydrogen
fluoride in the gaseous phase :
FeF + Hjv*2HF 4- Fe Fe 4- 2HF^FeF + H
2 8 2
T° K. . . . . 773° 873° 973° 773° 973°
jo . . . . .. 4-0 9-3 21-5 4-7 21-3
The reduction of ferrous fluoride by hydrogen is an endothermic reaction.
H. Schulze said that the anhydrous fluoride at a red-heat is not attacked by oxygen,
but C. Poulenc observed that the anhydrous salt furnishes ferric oxide when heated
in air or in water vapour. The salt dissolves slowly and sparingly in water, and the
salt in aq. soln. is readily hydrolyzed with the deposition of hydrated ferric oxide.
J. J. Berzelius, A. Scheurer-Kestner, and C. Poulenc observed that the hydrated
salt decomposes when it is heated in air, forming ferric oxide, and this oxide is also
produced when the hydrated salt is heated in hydrogen at 80°, but at a higher temp.,
it is reduced to iron. J. Ia. Gay Lussac and L. J. Thenard, J. J. Berzelius, and
C. Poulenc added that the hydrated salt also dissolves sparingly in water ; and
that if hydrofluoric acid be present the salt is more readily dissolved than it is in
water alone.
F. Fichter and A. Goldach studied the oxidation of ferrous fluoride by fluorine.
O. Ruff and E. Ascher found that neither bromine nor iodine has any perceptible
action on ferrous fluoride. G. Gore found that anhydrous ferric fluoride is neither
attacked nor dissolved by liquefied hydrogen fluoride ; and C. Poulenc found that
in hydrogen fluoride at 1100°, crystals of ferrous fluoride are formed. The
anhydrous salt and the hydrate dissolve in hydrofluoric acid—vide supra—more
readily than they do in water, and the aq. soln. when treated with potassium
permanganate, or exposed to air, forms ferric fluoride. A. Scheurer-Kestner
observed that a soln. of ferrous fluoride in an excess of hydrofluoric acid forms
ferric fluoride. When the fluoride is heated in hydrogen chloride, O. Ruff and
E. Ascher observed that ferrous chloride is formed, but, at ordinary temp., ferrous
chloride is converted into the fluoride : FeF +2HCl^FeCl +2HF. The
2 2
anhydrous salt is attacked with difficulty by cone, hydrochloric acid ; but
C. Poulenc said that the hydrated salt is readily dissolved by this acid.
O. Ruff and E. Ascher observed that anhydrous ferrous fluoride does not react
with sulphur to any great extent ; if the product be treated with dil. hydrochloric
acid, traces of hydrogen sulphide are formed. C. Poulenc observed that when
heated with hydrogen sulphide, ferrous fluoride forms ferrous sulphide ; O. Ruff
and E. Ascher, that at a red-heat, sulphur dioxide only deepens the colour of the
salt ; and C. Poulenc, that when heated with cone, sulphuric acid ferric sulphate is
formed. The tetrahydrate is readily soluble in sulphuric acid. O. Ruff and
E. Ascher found that ferrous fluoride is slowly decomposed by ammonia at a dull
red-heat, but, according to W. Biltz and E. Rahlfs, the tetrahydrate forms with
liquid ammonia at —78*5°, or gaseous ammonia at 0°, ferrous aquopentamminOs,
fluoride, FeF .5NH .H 0, which, at —21°, —11°, and 0°, has a heat of formation
2 3 2
of 9*8 CaIs., and the dissociation press, respectively 24, 51, and 113 mm. The
sp. gr. is 1*477 at —21°, and the mol. vol. 133-4. Above 0°, this salt passes into