IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: Bismuth formate with Potassium formate, Formic acid and Water

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Components:
   (1) Potassium formate; KCHO2; [590-29-4]  NIST Chemistry WebBook for detail
   (2) Bismuth formate; Bi(CHO2)3; [25573-24-4]  NIST Chemistry WebBook for detail
   (3) Formic acid; CH2O2; [64-18-6]  NIST Chemistry WebBook for detail
   (4) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Chaplygina, N.M.; Itkina, L.S., Zh. Neorg. Khim. 26, 1097-1103 (1981).

Variables:

   Concentration = Composition at 25 ºC

Prepared By:
   Chr. Balarew and St. Trendafilova

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)   

Solubility values in the Bi(CHO₂)₃-KCHO₂-CH₂O₂-H₂O system at 25 °C.

Chemical1	Phase	Mass Fraction w1	m1 [mol kg-1]a	Chemical2	Mass Fraction w2	m2 [mol kg-1]a	Chemical3	Mass Fraction w3	m3 [mol kg-1]	Solid Phase(s)b
CH2O2	Liquid	0.0	0.0	KCHO2	81.82	53.51	Bi(CHO2)3	0.0	0.0	A
CH2O2	Liquid	4.85	5.85	KCHO2	77.00	50.84	Bi(CHO2)3	0.14	0.023	A+B+C
CH2O2	Liquid	5.16	4.07	KCHO2	67.13	28.96	Bi(CHO2)3	0.15	0.016	B+C
CH2O2	Liquid	7.17	4.99	KCHO2	61.43	23.40	Bi(CHO2)3	0.18	0.017	B+C
CH2O2	Liquid	13.72	9.062	KCHO2	53.13	19.20	Bi(CHO2)3	0.25	0.022	B+C
CH2O2	Liquid	23.62	15.77	KCHO2	43.48	15.88	Bi(CHO2)3	0.35	0.031	B+C
CH2O2	Liquid	24.48	16.59	KCHO2	43.08	15.98	Bi(CHO2)3	0.38	0.034	B+C
CH2O2	Liquid	29.26	22.05	KCHO2	41.51	17.12	Bi(CHO2)3	0.40	0.040	B+C
CH2O2	Liquid	36.57	34.63	KCHO2	40.02	20.73	Bi(CHO2)3	0.46	0.058	B+C
CH2O2	Liquid	49.15	111.0	KCHO2	40.75	50.37	Bi(CHO2)3	0.48	0.145	B+C
CH2O2	Liquid	57.14	542.2	KCHO2	40.10	208.2	Bi(CHO2)3	0.47	0.597	B+C
CH2O2	Liquid	59.34	1386	KCHO2	38.70	494.8	Bi(CHO2)3	1.03	3.22	C
CH2O2	Liquid	57.14	226.6	KCHO2	36.67	79.57	Bi(CHO2)3	0.71	0.38	C
CH2O2	Liquid	51.63	94.04	KCHO2	35.86	35.74	Bi(CHO2)3	0.58	0.141	C
CH2O2	Liquid	45.58	48.57	KCHO2	31.26	18.23	Bi(CHO2)3	2.77	0.395	C
CH2O2	Liquid	43.14	45.64	KCHO2	34.94	20.23	Bi(CHO2)3	1.38	0.195	C
CH2O2	Liquid	35.59	33.44	KCHO2	40.87	21.01	Bi(CHO2)3	0.41	0.52	C
CH2O2	Liquid	29.21	16.88	KCHO2	31.24	9.877	Bi(CHO2)3	1.94	0.150	C
CH2O2	Liquid	28.68	16.25	KCHO2	30.07	9.326	Bi(CHO2)3	2.91	0.221	C
CH2O2	Liquid	27.77	16.92	KCHO2	35.15	11.72	Bi(CHO2)3	1.41	0.115	C
CH2O2	Liquid	21.75	14.05	KCHO2	44.20	15.62	Bi(CHO2)3	0.41	0.035	C
CH2O2	Liquid	20.93	9.393	KCHO2	27.76	6.817	Bi(CHO2)3	2.89	0.173	C
CH2O2	Liquid	15.40	5.994	KCHO2	23.11	4.922	Bi(CHO2)3	5.66	0.295	C
CH2O2	Liquid	13.86	8.083	KCHO2	48.67	15.53	Bi(CHO2)3	0.21	0.016	C
CH2O2	Liquid	11.74	6.570	KCHO2	48.86	14.96	Bi(CHO2)3	0.57	0.043	C
CH2O2	Liquid	1.51	0.505	KCHO2	33.30	6.089	Bi(CHO2)3	0.16	0.007	C
CH2O2	Liquid	4.75	1.50	KCHO2	25.60	4.435	Bi(CHO2)3	1.02	0.043	C+D
CH2O2	Liquid	5.68	1.80	KCHO2	23.87	4.129	Bi(CHO2)3	1.71	0.072	C+D
CH2O2	Liquid	6.54	2.16	KCHO2	26.02	4.693	Bi(CHO2)3	1.52	0.067	C+D
CH2O2	Liquid	12.52	4.797	KCHO2	25.60	5.368	Bi(CHO2)3	5.17	0.265	C+D
CH2O2	Liquid	17.51	7.119	KCHO2	23.95	5.328	Bi(CHO2)3	5.09	0.277	C+D
CH2O2	Liquid	20.76	9.315	KCHO2	25.19	6.185	Bi(CHO2)3	5.62	0.337	C+D
CH2O2	Liquid	47.82	53.34	KCHO2	29.88	18.24	Bi(CHO2)3	2.82	0.421	C+D
CH2O2	Liquid	55.89	96.08	KCHO2	30.28	28.48	Bi(CHO2)3	1.19	0.274	C+D
CH2O2	Liquid	54.91	71.40	KCHO2	27.17	19.33	Bi(CHO2)3	1.21	0.210	D
CH2O2	Liquid	48.76	38.64	KCHO2	22.81	9.891	Bi(CHO2)3	1.01	0.107	D
CH2O2	Liquid	40.68	29.95	KCHO2	27.10	10.92	Bi(CHO2)3	2.71	0.267	D
CH2O2	Liquid	39.22	19.57	KCHO2	16.36	4.468	Bi(CHO2)3	0.88	0.059	D
CH2O2	Liquid	36.86	18.36	KCHO2	18.18	4.955	Bi(CHO2)3	1.33	0.089	D
CH2O2	Liquid	32.53	18.39	KCHO2	25.59	8.486	Bi(CHO2)3	4.63	0.361	D
CH2O2	Liquid	27.46	13.34	KCHO2	24.68	6.559	Bi(CHO2)3	3.12	0.203	D
CH2O2	Liquid	23.10	10.79	KCHO2	25.02	6.400	Bi(CHO2)3	5.31	0.332	D
CH2O2	Liquid	21.62	9.453	KCHO2	23.42	5.603	Bi(CHO2)3	5.26	0.308	D
CH2O2	Liquid	19.78	6.792	KCHO2	15.15	2.847	Bi(CHO2)3	1.79	0.082	D
CH2O2	Liquid	19.53	5.909	KCHO2	7.91	1.310	Bi(CHO2)3	0.74	0.299	D
CH2O2	Liquid	19.22	7.630	KCHO2	22.09	4.798	Bi(CHO2)3	3.95	0.210	D
CH2O2	Liquid	18.20	5.711	KCHO2	11.66	2.002	Bi(CHO2)3	0.89	0.037	D
CH2O2	Liquid	17.14	6.937	KCHO2	23.30	5.160	Bi(CHO2)3	5.87	0.318	D
CH2O2	Liquid	11.30	4.173	KCHO2	23.90	4.830	Bi(CHO2)3	5.96	0.294	D
CH2O2	Liquid	78.18	1049	KCHO2	20.14	147.8	Bi(CHO2)3	0.06	0.11	D
CH2O2	Liquid	86.90	3433	KCHO2	12.53	270.9	Bi(CHO2)3	0.02	0.11	D
CH2O2	Liquid	93.43	3275	KCHO2	5.94	113.9	Bi(CHO2)3	0.01	0.05	D
CH2O2	Liquid	98.70	2841	KCHO2	0.54	8.5	Bi(CHO2)3	0.005	0.02	D
CH2O2	Liquid	29.00	18.99	KCHO2	37.28	13.36	Bi(CHO2)3	0.53	0.046	C
CH2O2	Liquid	26.78	17.20	KCHO2	38.95	13.69	Bi(CHO2)3	0.43	0.037	C

Notes:
   ^a  The molality values were calculated by the compilers.
   ^b  The solid phases are: A = KCHO₂; B = KCHO₂•CH₂O₂; C = K2Bi(CHO₂)₅; D = Bi(CHO₂)₃.

Method/Apparatus/Procedure:
   The isothermal method was used. Equilibrium was reached in 3 weeks. The potassium content of both phases was determined by flame photometry. The bismuth content was determined by complexometric titration using Pirokatechin violet as indicator. The formate content was determined by titration with 0.05 N NaOH after adding sodium oxalate to suppress the hydrolysis of the bismuth salts. The composition of the solid phases was determined by Schreinemakers method, by DT analysis, IR spectroscopy and x-ray diffraction.

Source and Purity of Materials:
   Bi(CHO₂)₃ was prepared by neutralizing 40% p.a. grade formic acid with suprapure reagent grade Bi₂O₃. Potassium formate was prepared by neutralizing p.a. grade 85% formic acid with p.a. grade KOH. The salt was washed with ethanol and dried over sulfuric acid.

Estimated Errors:
   Solubility: No information is given
   Temperature: No information is given.

References:
   ¹C. I. Stalhandske, Acta Chem. Scand. 23, 1525 (1969).

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Last updated: February 18, 2015 (Created: August 17, 2007)