SOL'L'BILITY O F COPPER SULPHATE, RIALACHITE AND BURGIXDT PRECIPITATE I N APIIMOT\'IUM HYDROXIDE, C.iIIBOXATE A S D BICARBOXATE BY E . B . HOLLAND A S D G. M . GILLIG.4X
Introduction In connection n-ith a rather extended investigation of copper fungicides it was found necessary to determine the solubility of various copper compounds in ammonium hydroxide, carbonate and bicarbonate, and the results so obtained are offered as a contribution to the literature on cupranimoniums.
As Pennj- (17, p. 5 ) ' had shown 3 . 2 0 per cent ammonia (SH3) the most efficient for malachite, approximately that concentration of ammonia was employed in all three solvents. The strength of the solvents was determined by adding a given quantity to an excess of normal acid, and titrating back with normal alkali. using methyl orange as indicator. Precautions were taken to prevent loss of ammonia from the standardized solutions, hut occasional fortifying was found necessary. A teMperature of z 5OC. was adopted. but could not he maintained consistently in the laboratory. I n all cases the copper salt n-as added to a measured quantity of approximately a 3 . 2 j percent ammonia solvent in a 150 C . C . Erlenmeyer flask. stoppered, allowed to stand with occasional shaking to facilitate solution. diluted with mater to I O O c.c., and final readings taken after several hours. Solutions near saturation will often reprecipitate on standing, due to loss of ammonia from the liquid phase to the gaseous, therefore, the amount of solvent reported should esceed slightly that actually required for solution. For convenience the various determinations will be classified, first, according t,o the solvent, into ( I ) ammonium hydroxide, ( 2 ) ammonium carbonate, ( 3 ) ammonium bicarbonate, and secondly. according to the source of copper into, (a) copper sulphate, (b) malachite, (c) Burgundy precipitate. 1. Ammonium Hydroxide ( a ) C o p p e r Sulphale The amount of ammonium hydroxide (SH,OH) and of ammonia (NH,) required to give clear solutions with 1.0 gram and 0.1 gram of powdered, selected crystals of C. P. copper sulphate (Cu 2 j . 3 7 per cent, equivalent t o 99.66 per cent theoretical) dissolved in approximately 3 . 2 j per cent solution of SH,, anti subsequently diluted to I O O C.C.and the calculated amount for each I O O C.C.of added n-ater between these limits are reported in Table I.
Reference is made bv number \italic) t o "Literature cited"
SOLUBILITY O F COPPER SALTS IN AMSIONIA
729
TABLE I Ammonium hydroxide and ammonia required to give a clear solution with copper sulphate Gram mols Gram mols Gram mols Gram mols
of of of of
Theoretical ratio ammonium hydroxide per mol of copper sulphate ammonia per mol of copper sulphate ammonium hydroxide per (n)' mols copper ammonia per (n)' mols copper
Experimental data Copper sulphate to a clear solution in IOO C.C. Mols of ammonium hydroxide Mols of ammonia Grams of ammonium hydroxide Grams of ammonia C.C. of commercial ammonia water (Sp. gr. 0.90)
0 . I 403
5
0.06821 0
55133
0.26793
I , o Gms. 0 .I Gms. 4 5 23.0 4.5 23.0 0.631j8 0 . 3 2 2 8 1
o 30695 1.26
0 . I 5688
0.65
Calculated Grams of ammonium hydroxide per I O O C.C. of water Grams of ammonia per I O O C.C. of water C.C. commercial ammonia water (Sp. gr. 0.90)
0.28850 0.14021 0 . 58
The amount of commercial ammonia water (Aqua Ammoniae Fortior) specific gravity 0.90, is calculated on the minimum requirement of the U.S. P. (23, pp. 56, 544) or 2 7 per cent ammonia (KH,) by weight, equivalent to 0.2429 grams in I C.C. at 2 j0/z5OC. Millardet and David (IC),Lasserre (13) and Butler ( 2 ) p. 238) obtained for I per cent solution of copper sulphate 1 . 5 3 ~I . j o and 1.50 C.C.of ammonia water respectively, a quantity larger than was required in this laboratory. Horn (11,p. 476) cites 5.48 mols of ammonia for a 1.25 per cent solution. That a greater proportion of ammonia is required to maintain equilibrium on dilution is generally recognized, Pickering (7, p. IS) obtained 1.6 C.C.and Butler (2, p. 238) 0.7 C.C. of ammonia water for a 0.1per cent solution of copper sulphate, results appreciably higher than that reported. There is naturally a difference of opinion as to the reactions involved in the production of cuprammonium sulphate, but the following are intended to embrace substantially the views of Chester (4, p. 68), Dawson and hlcCrne (5, p. 1 2 5 8 ; 6, p. 1666), Horn (12, p. 475) and Prescott and Johnson (22, p. 106).
+
+
(I) 4CuS04jHzO 6NH4OH = C U S O ~ . ~ C U ( O H ) ~ . H Z3(NH4)2 O IsHz0 (2) C U S O ~ . ~ C U ( O H ) ~ . H ~3(NH,)zSO, O z N H ~ O H 4Cu(OH)z 4("4)zSO4 HzO (3) 4Cu(OH)z 4(h",),SO, (8+n)KH4OH = ~ C U ( N H ~ ) Z ( O H ) Z ~ ( N H ~ z S On(NH4OH) ~ 8&0 SOa
+
+
+
+
+
+
+
+
+
The number of mols of copper in the compound.
+
730
E. B . HOLLAND A S D G . 111. GILLIGAS
4Cu(NH3),(OH), + 4 ~ ~ H , ) 2 S 0+. 1n(?LTH40H) = 4Cu(KH3),S04 + n(NH,OH) + 4 H 2 0 C U S O ~ . ~ C U ( O H+ ) ~ .3(NH4)2 H~~ ( 5 ) 4Cu(?JH3),SO,HzO + 5Hz0 SO,+ I O X H ~ O H (4)
H20
=
By analogy one may presuppose in reaction ( I ) 5CuO. SO3 and 1oCu0 7 . 2 mols of ammonia as in the case of fixed alkalies. shown by Pickering (18, p. 1983: 29, pp. 1991, 1997, 2ooo;Rl,pp. 1852, I 8 j j ; 9, pp. 26, z 7 ) , but there is no evidence to that effect. In reaction (3) (n) must be 0.5 mols per mol of copper sulphate for a I per cent solution, as shown in Table 1) but as (n) increases rapidly on dilution, dissociation phenomena must be involved. Furthermore dry commercial cuprammonium sulphate, Cu(XH3)&304.H20, although an unstable product, required only a small amount of additional ammonia to clear a I per cent solution which would tend to confirm the value of (n). Theoretically the precipitate obtained on dilution, reaction (;), should be largely basic sulphate, but in some instances at least considerable hydroxide results which on filtering and drying is readily converted into basic carbonate, as shown by the analysis of the following sample prepared in the laboratory.
so3 from 6.4 mols and
Per cent Cupric oxide, CuO Sulphuric trioxide, SOa Carbon dioxide, CO? Water by difference, HzO
69,47 6.72
9.27 14.54 100.00
Hypothetical combinations Water, HzO Tribasic copper sulphate, 4CuO.SO 4 H z 0 Basic copper carbonate, C U C O ~ . C ~ ( O H ) ~ Copper hydroxide, Cu(OH)?
2.606 39'483
46'594 11.317 100.000
With proper control, however, and less attention to yield a higher proportion of basic sulphate should be recovered. The solubility of tribasic copper sulphate (,rCu0.S03.4H20)in ammonia could not be determined as a sample of satisfactory quality was not obtainable at the time. ( b ) N'alnchite The amount of ammonium hydroxide and of ammonia required to give clear solutions with 0.5 gram and 0.1gram of Merck's, ('. P., green copper carbonate (moisture 1 . j 8 per cent, ('u 54.30 per cent, equivalent to 94.4j per cent pure) dissolved in approximately 3.2 j per cent solution of ammonia,
SOLUBILITY OF COPPER 8.4LTS I N AMYOh'IA
73 1
and subsequently diluted to I O O c.c., and the calculated amount for each 100 C.C. of added water between these limits are reported in Table 11. As the quantity of 3.25 per cent ammonia necessary for I gram of malachite would exceed 100 c.c.. 0.5 gram was the maximum amount employed. Technical or commercial malachite is said to contain only 50 to 5 2 per cent of copper.
TABLE I1 Ammonium hydroxide and ammonia required to give a clear solution with malachite Gram Gram Gram Gram
rnols of mols of mols of mols of
Theoretical ratio ammonium hydroxide per mol of malachite ammonia per mol of malachite ammonium hydroxide per (n)' mcls of copper ammonia per (n)' mols of copper
Experimental data 3Ialachite to a clear solution in 100 C.C. 3101s of ammonium hydroxide Xols of ammonia Grams of ammoniuni hydroxide Grams of ammonia C.C.of commercial ammonia water (Sp. gr. 0.90)
0 .j
Gms.
60.0 60.0 4.75440 2.31030 9.51
0.15848 0.07jOI o 27566 0.13396
0 .I
Gms.
65.0
65.0 I
.03012
0.50057
2.06
Calculated Grams of ammonium hydroxide per I O O C.C.of mater 0.09905 Grams of ammonia per I O O C . C . of water 0.04814 C.C.of commercial ammonia water (Sp. pr. 0.90) 0.20 Investigators do not agree as to the reaction involved in the solution of malachite in ammonia. Gastine i l l , p. 1 1 j ) claims the resultant is cupramrrionium carbonate; Pickering (8, p. 20) mainly cuprammonium carbonate; Chester ( 4 , p. 68) cuprammonium carbonate and cuprammonium hydroxide, and Butler ( 2 , p. 242) cuprammoninni hydroxide. Mellor (15, pp. I j r , 1 5 2 , 2 7 5 ) cites considerable data, but to what extent applicable is uncertain. Evidently cuprammoniuin carbonate could not be formed in entirety unless sufficient carbon dioxide was absorbed to satisfy the reaction ( I ) , but a mixture of cuprammonium carbonate and of cuprammonium hydroxide (z), or cuprammonium hydroxide alone, (3) offers a more feasible hypothesis. ( I )
+
CUCO~.CU(OH)? CO, CuCOa.Cu(OH)z
+
4SH,OH
1
+
~CU(XH~)~CO jHQO ~
+ 6KHqC)H = C U ( N H ~ ) ~ C+O C~ U ( S H ~ ) ~ ( O H ) ~ ~ C U ( X H ~ ) ~ ( O+ H )NH4HCOa ,
+ 6H20 (3) C U C O ~ . C U ( O H+ ) ~ 9NH,OH + iHzO (2)
=
=
T h e number of mols of copper in the compound.
E. B. HOLLAND AND G. M. GILLIGAN
73 2
As the amount of ammonia entering combination constitutes but a small proportion of that required for solution, due probably to limited surface area, and the resistance of malachite to dissociation, the mols reported, Table 11, are of little significance in designating the reaction. Reaction (3) seems the most probable, however, as the solution dissolves cellulose, does not deposit malachite on standing, according to Butler (2, p. z ~ z ) ,and yields the hydroxide on dilution. A precipitate prepared in the laboratory by dilution, filtration, and drying in vacuo a t room temperature, gave a blue resultant which contained 61.98 per cent of copper, and a trace of carbon dioxide equivalent to about y j per cent cupric hydroxide. The carbon dioxide content must vary with the conditions of precipitation and exposure. The cuprammonium hydroxide formed with a small excess of ammonia is presumably the diammino obtained by Dawson and McCrae (a, p. 1 2 j7), and by Bonsdorff ( I ) , but with a large excess of ammonia the tetrammino is more probable as shown by Bonsdorff. The solubility of azurite (zCuC03.Cu(OH)2) in ammonia could not be determined as the only sample available contained I 2 . I 2 per ten.' J f ammonia insoluble matter which masked the end point.
(c) Burgundy Precipitate The amount of ammonium hydroxide and of ammonia requked to give clear solutions with aliquots of washed Burgundy precipitate, equivalent to 1.0gram and 0.1 gram of copper sulphate, dissolved in approximately 3.25 per cent solution of ammonia, "3, and subsequently diluted to IOO C.C. and the calculated amount for each IOO C.C.of added water between these limits, are reported in Table 111. The Burgundy mixture (soda Bordeaux, bouillie Bourguignonne) was prepared according to Masson (14, p. 816) as modified by Pickering ( I O , p. 86; 20, pp. 1 4 1 2 , 1414,1428).
+
sCuS04jH20 8Na2C03~oH20= gCu0.2CO2.6H~O gXa2SO4IoH20 6KaHCOa 46H20
+
+
+
Particular care was observed in gradually adding a cool, dilute solution of copper sulphate to a similar solution of sodium carbonate in order to reduce the loss of carbon dioxide to a minimum, and to favor the formation of a basic carbonate. The reverse procedure is likely to yield more or less basic sulphate. The precipitate was allowed to coalesce, filtered, washed substantially free from sodium sulphate and sodium bicarbonate, transferred to a graduated flask, and made to volume. Upon standing the washed precipitate is gradually converted into malachite. The results are reported in terms of copper sulphate, less small unavoidable errors due to incomplete precipitation of the copper and mechanical losses, but assuming that one gram of copper sulphate yields approximately 0.47 j j o grams of basic carbonate ( j C u 0 . Z C ~ ~ . ~ the H ~results O ) could be readily recalculated to the latter basis.
SOLUBILITY OF COPPER SALTS I N AMMONIA
733
TABLE111 Ammonium hydroxide and ammonia required to give a clear solution with washed Burgundy precipitate, in terms of copper sulphate Theoretical ratio Gram mols of ammonium hydroxide per mol of copper sulphate 0.I403 5 0.06821 Gram mols of ammonia per mol of copper sulphate Gram mols of ammonium hydroxide per (n) mols of copper 0,55133 Gram mols of ammonia per (n) mols of copper 0.26793 Experimental data 0 .I Gms. I . o Gms. Copper sulphate to a clear solution in I O O C.C. Mols of ammonium hydroxide 18.5 34.0 Mols of ammonia 18.j 34.0 Grams of ammonium hydroxide 2.59648 0.47719 Grams of ammonia I . 26189 0.23191 C.C. of commercial ammonia water (Sp. gr. 0.90) 5.20 0.95 Calculated 0.24171 Grams of nmmonium hydroxide per I O O C.C. of water qrams of ammonia per IOO C.C. of water 0,11747 0.48 C.C. of comluarcial ammonia water (Sp. gr. 0.90) The reaction for solution is presumably similar to that of malachite. The soluhhty of sodium bicarbonate Bordeaux (Bordeaux bouillie celeste), (3,p. 291;10, p. 1414)precipitate in ammonia was not determined as the precipitation was considered too variable and incomplete to warrant the examination. The solubility on a one per cent basis of copper sulphate, malachite and washed Burgundy precipitate, and of the copper present, in ammonium hydroxide and its ammonia content, is summarized in Table IV, together with the dilution or hydrolytic equivalent. TABLE IV Solubility and hydrolytic equivalent of the copper compounds in ammonium Ammonium hydroxide On a one per cent basis
Copper sulphate Hydrolyticequivalent per I O O c.c., 1.0to 0.1 gram Copper in copper sulphate' Hydrolytic equivalent Malachite Hydrolytic equivalent per I O O c.c., 0.5 to 0.1 gram Copper in malachitel Hydrolytic equivalent Washed Burgundy precipitate Hydrolyticequivalentper I O O C . ~ . , 0.48 to0.048gram Copper in washed Burgundy precipitate Hydrolytic equivalent 1
hydroxide
Grams 0.63158 0.28850 2 . 4894n
1.13717 9.50880 0.09905 17.51160 0.18241
5.45823 0.24171 10.23482 0,45323
Calculated on a theoretical basis from the copper in the product tested.
Ammonia
Grams 0.30695 0.14021 I . 20989 0.55266 4.62060
0.04814 8,50939 0.08866 2.65270 0.11747 4.97412 0.22027
E . B . HOLLASD B S D G . 11, GILLIGAN
734
Summary of Results with Ammonium Hydroxide The solubility of malachite, washed Burgundy precipitate, and copper sulphate in ammonium hydroside, increases in the order named or directly with their cliaperaion. Conversely the amount of amnionium hydrositlc required t o form soluhle cupranimonium tlecreases in the same order. 2. The solubility of the copper in ammonia is in the same order but in ore m i f or iii . 3. Xnimonium hydroside soluble cuprammnniums are unstable on dilution. The ',hydrolytic equivalent" or the amount of solvent required to counteract dilution. is in the reverse order of the solubilities and, in terms of copper and of aninionia, fairly proportional. 4. Ammonium hydroside solu1)le c~praiiiiiioniiimsare unstahle in relatively high concentrations of ammonia, and unrler the influence of heat, decotnposing with the formation of dicupric hydroside or ositle. I.
2 . Ammonium Carbonate The solubility of the several copper compounds in ammonium carbonate was determined in the same manner as in ammonium hydrositle. dmmoniuni carbonate (Aiiimonii C'arhonas) consists of varying proportioris of ammonium bicarbonate I S H 4 H r 0 3 )and ammonium carbamate IXH,.SH?CO?).but is generally considered as of equal mols and substantially of equal parts hy weight i 9 . 0 4 8 : j8.064. The amount of commercial ainmnnium carbonate is calculated on the minimum requirement of the 8. P. i.?, p p . 4;. 48)"to yield 30 per cent of animonia ( S H 3 ) " h yweight, equivalent to 9 2 . 2 4 5 per cent theoretical. -1solution of approsiniately 3 . 2 5 per cent ammonia iSHai content was emploj-ed and the copper salt added to the solvent, aiming to produce cuprammonium carbonate. Loss of carbon tlioside could not be entirely prevented however.
r.
(a) Copper Sulphate
TABLE V Ammonium carbonate required to give a clear solution with copper sulphate Gram mols of Gram mols of Gram mols of Gram mols of
Theoretical ratio ammonium carbonate per mol of copper sulphate ammonia per mol of copper sulphate ammonium carbonate per (n) rnols of copper ammonia per in) mols of copper
Esperimental data Copper sulphate to a clear solution in I O O C.C. Mols of ammonium carbonate Mols of ammonia Grams of ammonium carbonate Grams of ammonia Grams of commercial ammonium carbonate
I
.o
Gms.
7.5 I .
jj293
I , ;I
2.47148 0 . 2 6 j93
0.I
Gms.
3.0 9.0
2 . j
0 .~
0.6291j 0.0682 I
I j 8I
0 . I887 j
0.06139 0 . 2 0
73 5
SOLUBILITY O F COPPER SALTS I N AMMOKIA
TABLE 5’ (continued) Calculated Grams of ammonium carbonate per IOO C.C. of water Grains of ammonia per 100 C.C. of water Grams of commercial ammonium carbonate
0,03495 0.01137
0.04
Assuming that cuprammonium carbonate is formed in entirety, the following tentative reaction, complying with the results obtained with a one per cent solution of copper sulphate, Table V, is suggested:
+
+
~ C ~ S O A S H ? OjiSH4HC03SH4SHpCOg = Z C U ( X H ~ ) ~ C Oz (~N H ~ ) ~ S O ( 7KHIHCO3 COS 6H?O
+
+
+
Four mols of ammonium carbonate t o 3 of copper sulphate would satisfy the equation, but evidently greater excess is necessary for the reaction under the conditions employed. On eiaporation the solution appears to yield malachite.
+
+
z C U ( K H ~ ) ? C O ~z(SHJ)?SOA HzO 4SH3 CO,
+
+
=
CuCO3. Cu(OH)g
+ z(NHJ?SOA
A one per cent solution of commercial cuprammonium sulphate required about 0.5 mols of ammonium carbonate per mol of sulphate to clear, in which case only a small proportion a t best could have been converted into cuprammonium carbonate. ( b ) Malachite TABLE
TI
Ammonium carbonate required to give a clear solution with malachite
Gram Gram Gram Gram
mols mols mols mols
of of of of
Theoretical ratio ammonium carbonate per mol of malachite ammonia per mol of malachite ammonium carbonate per (n) mols of copper ammonia per (n) mols of copper
Experimental data Malachite to a clear solution in I O O C.C. Mols of ammonium carbonate Mols of ammonia Grams of ammonium carbonate Grams of ammonia Grams of commercial ammonium carbonate Calculated Grams of ammonium carbonate per IOO C.C. of water Grams of ammonia per I O O C.C. of water Grams of commercial ammonium carbonate
I
. o Gms.
0.71041 0.07701
1.23574 0.13396
0 .I
5.0
5.0
Ij.0
15.0
3,55205
Gms.
1.15515
0.35521 0.I 1 j 5 2
3.85
0.39
0.00000 0.00000 0.00000
E. B. HOLLAND AND G . M. GILLIGAS
736
The following tentative reaction is suggested as complying with the results secured with a one per cent solution, Table VI.
+ jX”aHCO~iKH~XH2C02+ 5HzO + 2NH40H
CUCO~.CU(OH)Z 9KH4HC03
+
=
~CU(NH~)~CO~
Four mols of ammonium carbonate to 3 mols of malachite would furnish sufficient ammonia to satisfy the equation but not for the reaction. On evaporation the solution apparently yields malachite or other basic carbonate. ( c j Burgundy Preczpatate
The >Fashed Burgundy precipitate was prepared as previously described, and the solubility determined on aliquots. The results are reported in terms of copper sulphate, but may be recalculated to basic carbonate (jCuO.2C01 6H20), assuming that I gram of copper sulphate yields approximately 0.47 j f o grams of basic carbonate.
TABLE T’II Ammonium carbonate required to give a clear solution with washed Burgundy precipitate, in terms of copper sulphate Theoretical ratio Gram mols Gram mols Gram mols Gram mols
of of of of
ammonium carbonate per mol of copper sulphate ammonia per mol of copper sulphate ammonium carbonate per (n) mols of copper ammonia per (n) mols of copper
0.6291 7
0.0682
I
2,47148 0.26793
Experimental data Copper sulphate to clear solution in I O O C.C. lllola of ammonium carbonate Mols of ammonia Grams of ammonium carbonate Grams of ammonia Grams of commercial ammonium carbonate
I.o
Gms.
0 .I
Gms.
3.33
3.33
10.0
10.0
2.09723 0.68210 2.27
0.20972
0.06821 0.23
Calculated Grams of ammonium carbonate per 100 C.C. of water Grams of ammonia per I O O C.C.of water Grams of commercial ammonium carbonate
0.00000 0.00000 0.00000
The solubility, on a one per cent basis, of copper sulphate, malachite and washed Burgundy precipitate and of the copper present, in ammonium carbonate and its ammonia content is summarized in Table VIII, together with the dilution or hydrolytic equivalent.
737
SOLUBILITY O F COPPER SALTS I N AMMONIA
TABLE VI11 Solubility and hydrolytic equivalent of the copper compounds in ammonium carbonate Ammonium carbonate
On a one per cent basis
Copper sulphate Hydrolytic equivalent per IOO c.c., 1.0 to 0.1 gram Copper in copper sulphate' Hydrolytic equivalent Malachite Hydrolytic equivalent per I O O c.c., 1.0 to 0.1 gram Copper in malachite' Hydrolytic equivalent Washed Burgundy precipitate Hydrolytic equivalent per 100 c.c., 0.48 to 0.048 gram Copper in washed Burgundy precipitate Hydrolytic equivalent
Ammonia
Grams
Grams
1.57293 0.03495 6.19996
0.51158 0.01137
0.13776
0.04482
2.01648
3.55205
1,15515
0.00000
0.00000
6.54141
2.12735
0.00000
0.00000
4.40872
1.43389
0,00000
0.00000
8.26687
2.68871
0.00000
0.00000
Summary of Results with Ammonium Carbonate I. The solubility of washed Burgundy precipitate, malachite and copper sulphate in ammonium carbonate increased in the order named, but is more uniform than in the case of ammonium hydroxide. The lower solubility of Burgundy precipitate (gCuO.zC02.6H20) as compared with malachite (CuC03.Cu(OH)?)may be due in part to the lower ratio of C 0 2 : Cu, as the physical character of the former is naturally more promising. 2. The solubility of the copper in terms of ammonia is fairly constant, and in marked contrast to ammonium hydroxide in this respect. 3 . Ammonium carbonate soluble cuprammoniums are more stable on dilution than the ammonium hydroxide soluble. Copper sulphate required a small excess of solvent to prevent partial hydrolysis, but malachite and Burgundy precipitate did not require any between the limits tested. 4. Ammonium carbonate soluble cuprammoniums are less likely to decompose with the formation of cupric oxide than ammonium hydroxide s o h ble
.
3. Ammonium Bicarbonate
Ammonium bicarbonate (NH4HC03) was also employed as a solvent in the same way as ammonium carbonate. There is no prescribed standard, but as the compound is relatively more stable than the carbonate, 95 per cent of the theoretical ammonia content was adopted as a reasonable requirement for the commercial product, equivalent to 20.47 per cent of ammonia ("3) by weight. 1
Calculated on a theoretical baais from the copper in the product tested.
E. B. HOLLAXD h S D G. 51. GILLIGAN
738
(a)
Copper Sulphate
TABLE I S Ammonium bicarbonate required to give a clear solution with copper sulphate
Gram Gram Gram Gram
mols mols mols mols
of of of of
Theoretical ratio ammonium bicarbonate per mol of copper sulphate ammonia per mol of copper sulphate ammonia bicarbonate per (n) mols of copper ammonia per (n) mols of copper
Experimental data Copper sulphate to a clear solution in I O O C.C. 9101s of ammonium bicarbonate Mols of ammonia Grams of ammonium bicarbonate Grams of ammonia Grams of commercial ammonium bicarbonate
I .o C h s . 8.5 8.5 2.69068 0 . j79j9
2.83
('alculated Grams of ammonium bicarbonate per 100 C . C . of nater Grams of annnonia per I O O e.c. of water Grams of comrnercial ammonium bicarbonate
0 . 3 I 6jj
0.06821 1.24348 0.26j93 0 ,I
Gms.
1 2 . 0
12.0
j986 0.0818j 0.3
0.40
0.111C)y
0.02666 0.13
The following tentative reaction is suggested as complying with the results obtained with a one per cent solution, Table IS. ~ C U S O ~ ~ H I~jSH4HC03 O = z C U ( K H ~ ) ? C O ~z(SHI)?SOA 9SH4 HCO, 6C'O2 16H?0 Four mols of ammonium bicarbonate to I mol of copper sulphate would furnish sufficient ammonia to satisfy the equation, but not for the reaction.
+
+
+
+
+
( b ) Malachite
TABLE S Ammonium bicarbonate required to give a clear solution with malachite Gram mols of Gram mols of Gram mols of Gram mols of
Theoretical ratio ammonium bicarbonate per mol of malachite ammonia per mol of malachite ammonium bicarbonate per (n) mols of copper ammonia per (n) mols of copper
Experimental data Malachite to a clear solution in I O O C.C. 3101s of ammonium bicarbonate 1,101s of ainnionia Grams of ammonium bicarbonate Grams of ammonia Grams of commercial ammonium bicarbonate
0 .j
Grns.
0,35743 0 . 0j i 0 I
0.62174 0.13396 0 .I
1j.o
I5,O
15.0
Ij.0
Gms.
2.68073
0.j361j
0.57758
0.115j2
2.82
0.56
739
SOLUBILITY OF COPPER SALTS IS AMMONIA
TABLE X (continued) Calculated Grams of ammonium bicarbonate per IOO C.C. of water Grams of ammonia per I O O C.C. of water Grams of commercial ammonium bicarbonate
0.00000 0.00000
0.00000
As the quantity of solvent necessary for one gram of malachite would exceed I O O c.c., 0 . j gram was the maximum amount employed. The following tentative reaction is suggested as complying with the results obtained with a 0.5 per cent solution, Table x. C U C O ~ . C U ( O H ) ~ I ~ S H ~ H C=O z~ C U ( N H ~ ) ~ C O ~I I N H ~ H C O I 3Coz jHzO Four mols of ammonium bicarbonate to I mol of malachite would furnish sufficient ammonia to satisfy the reaction.
+
+
+
+
(c) Burgundy Precipitate
TABLEXI Ammonium bicarbonate required to give a clear solution with washed Burgundy precipitate, in terms of copper sulphate Theoretical ratio Gram mols of ammonium bicarbonate per mol of copper sulphate Gram mols of ammonia per mol of copper sulphate Gram mols of ammonium bicarbonate per (n) mols of copper Gram mols of ammonia per (n) mols of copper Experimental data Copper sulphate to a clear solution in IOO C.C. Mols of ammonium bicarbonate Mols of ammonia Grams of ammonium bicarbonate Grams of ammonia Grams of commercial ammonium bicarbonate
I . o Gms.
0.3 16j j 0.0682 I 1.24348 0.26793
0 .I
10.0
10.0
10.0 3.16550 0.68210 3.33
10.0
Calculated Grams of ammonium bicarbonate per I O O C.C. of water Grams of ammonia per IOO C.C. of water Grams of commercial ammonium bicarbonate
Gms.
0.31655 0.06821 0.33
0.00000
0.00000 0.00000
The solubility, on a one per cent basis, of copper sulphate, malachite and washed Burgundy precipitate and of the copper present in ammonium bicarbonate and its ammonia content, is summarized in Table XII, together with the dilution or hydrolytic equivalent.
740
E. B. HOLLAND AND G . 11. GILLIGAN
TABLE XI1 Solubility and hydrolytic equivalent of the copper compounds in ammonium bicarbonate On a one per cent basis
Ammonium bicarbonate
.hnmonia
Grams
Grams
Copper sulphate 2.69068 Hydrolytic equivalent per I O O c.c., 1.0to 0.1gram 0 . I I 199 Copper in a copper sulphate' 10.605j6 Hydrolytic equivalent 0,44143 Malachite 5.36116 Hydrolytic equivalent per I O O c.c., 0.5 to 0.1 gram o.ooooo Copper in malachite' 9.87378 Hydrolytic equivalent 0,00000 Washed Burgundy precipitate 6.65440 Hydrolytic equivalent per IOO c.c., 0.48 to 0.048 gram 0 . ooooo Copper in washed Burgundy precipitate 1z.4j;;8 Hydrolytic equivalent 0.00000
0.57979
0.02666 2.28j34 0.1oj08 1.1jj16 o.ooooo z.12j3j 0.00000 I
,43389
0 . ooooo
2.68871 0.00000
Summary of Results with Ammonium Bicarbonate I. The solubility of washed Burgundy precipitate, malachite and copper sulphate in ammonium bicarbonate increased in the order named, and is even
more uniform than with ammonium carbonate. The bicarbonate, however, proved less efficient' than the carbonate. 2. The solubility of the copper in terms of annnonia is nearly constant, but in a new order malachite, copper sulphate and Burgundy precipit,ate. The same amount of ammonia in bicarbonate and carbonate proved equally effective on the copper in malachite and on the copper in Burgundy precipitate, but the ammonia in the bicarbonate is less effective than in the carbonate, on the copper in copper sulphate. 3 . In the case of copper sulphate more bicarbonate was required to prevent hydrolysis than of carbonate, but with malachite and Burgundy precipitate no additional solvent was required between the limits tested. Summary of Results with the Different Solvents
The effectiveness of ammonium bicarbonate, ammonium carbonate I, and ammonium hydroxide on copper sulphate in producing soluble cuprammoniums increases in the order named, and hold equally true of the ammonia content, but not in the same magnitude. 2. The effectiveness of ammonium hydroxide, ammonium bicarbonate and ammonium carbonate on malachite increases in the order named, but the ammonia in carbonate and bicarbonate is equally effective. 3. The effectiveness of ammonium bicarbonate, ammonium hydroxide and ammonium carbonate on Burgundy precipitate increased in the order named, but the ammonia in carbonate and bicarbonate is equally effective. Calculated on a theoretical basis from the copper in the product tested.
SOLUBILITY O F COPPER SALTS IN AMYOSIA
741
4. The hydrolytic equivalent of the cuprammoniums decreases in the following order, copper sulphate-ammonium hydroxide, Burgundy precipitateammonium hydroxide, copper sulphate-ammonium bicarbonate, malachiteammonium hydroxide, and copper sulphate-ammonium carbonate. Malachite and Burgundy precipitate with ammonium carbonate and ammonium bicarbonate required no additional solvent between the limits tested. In terms of ammonia malachite-ammonium hydroxide preceded copper sulphate-ammonia bicarbonate, otherwise in the same order as above. In general the hydrolytic equivalent was inversely proportional to the amount required for solution. .Iloss. Agrzcullural Exp. Stalzon,
Amherst, M a s s .
LITERATVRE CITED (1)
K. Bonsdorff: Z. anorg. Chem., 41, 184 (19041.
0.Butler: Phytopath.. 7, 23j-238 (1917). “The Cuprammoniurn Kashes.” (3) E. Bourcart: “Insecticides, Fungicides and Keedkillers”, 2d ed. (1925). Revised by T. R . Burton. (4) F. D. Chester: J. llycol. 6, 23; Del. Agr. Espt. Sta. Rpt., 4, 6j-74 (1891). “The Copper Fungicides.” ( 5 1 H. 11. Dawson and J. JlcCrae: J. Chem. SOP.,77, 1239-1262(1900). “The Sature of Netal-ammonia Compounds in Aqueous Solutions.” (6)€1. 11. Danvon: J . Chem. SOC.,8 9 11; 1664-1674 (1906:. “The Sature of Ammoniacal Copper Solutions.” (71Duke of Bedford and 9. L-. Pickering: TVohurn Expt. Fruit Farm Rept. 11, 16-19(1910). “Copper Sulphate and .Immonia; Cuprammonium Sulphate.” (8) Duke of Bedford and S.I-. Pickering: Wohurn Espt. Fruit Farm Rept., 11,20-21(1910). “Copper Carbonate dissolved in .Immonia or in .Immonium Carbonate: Cupram.” f91 Duke of Bedford and S. I-.Pickering: Koburn Expt. Fruit Farm Rept., 11, 22-75 (19101. “Bordeaux JIixtures.” ( I O ) Duke of Bedford and S. Pickering: K o b u r n Expt. Fruit Farm Rept., 11, 86-92 (1910’1. “Soda Bordeaus.” ( I I I 0 . Gastine: Progr. .4gr. et Vit. (llontpellier), 4, 114-117 (1887). “Emploi du carbonate ammoniacal de cuivre contre le peronoapora.” ( 1 2 ) D 11.. Horn. Am. Chem !., 38, 475-489 (190;). “On Some Cuprammonium Salts IV. Cuprammonium Sulphate (13) Lasserre: J . .igr. Prat., Dec. 13 (1888). (14) Emile Masson: J. .Igr. ,Prat., 5 1 I. 811-816; Progr. Agr. et Vit., 4, 513 (1887). “Souveau proci.de Rourguignon contre le mildiou.” (15) ,J. 11.. Melior: “A Comprehensive Treatise on Inorganic and Theoretical Chemistry.” 3 (1923). (16).I. 1 I i l l ~ ~ dand e t E. David: Compt. rend. Cong. S a t l . Vit. [Bordeaux! Appendix, 60 (1886). Essais cornparatifs de divers procedes de traitement du mildiou.” (17) C. L. Penny: Del. Agr. Expt. Sta. ByL, 22, 3-16 (1893). “The Preparation of .Immoniacal Solution of Copper Sulphate. (181 S . I-.Pickering: J.Chem. .Sot., 91 11, 1981-1988‘19oj1. “The Interaction of Metallic Sulphates and Caustic Alkalis.” (19)S.r.Pickering: J. Chem. Soc., 91 11, 1988-2001i1907). “The Chemistry of Bordeaux Mixture.” (20) 8. I-. Pickering: J. Chem. Soc.. 95 11, 1409-1429(1909). “The Carbonates of Copper and the Cupricarhonates.” (21) 6 . I-.Pickering: J. Chem. Soc., 97 11, 18j1-1860( r g r o ) . “The Constitution of Basic Salts.” ( 2 2 ’ .I.B. Prescott and 0. C . Johnson: “Qualitative Chemical .Inalysis.” 6th ed. (19051. (23) S. Pharmacopoeia, loth Dee. Rev. (1926).
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