NIST-IUPAC Solubility Data Series

Potassium formate with Formic acid and Water (IUPAC SDS Volume 73)

SDS Volume

Volume 73. Metal and Ammonium Formate Systems, p None

Source Publication

Sas, T. M.; Rodina,G. L.; Velikodnyn, Yu. A.; Tr. IREA Moscow Ser. Reagents and specially pure substances 42, 168 (1980).

Conditions:

Temperature: 298.2 and 323.2 $\pu{K}$

Compiler:

T.A. Ageyeva

Methodology:

The isothermal method was used [1]. The formic acid content was determined by titration with $\pu{0.1 N} \ce{NaOH}$ using phenolphthalein as indicator. The $\ce{KCHO2}$ content was determined by titration with $\ce{NaOH}$ after passing the weighed sample through a chromatographic column. The water content was calculated by difference. The solid phase was identified by chemical, thermogravimetric, gas chromatographic and X-ray methods.

Sample Information:

Temperature: No information is given.

Measurement Errors:

Ambient temperature: No information is given.
Mass concentration (m/v) (1): ±0.5 mass%. Nothing else is specified.

Methodology Citation

¹ Othmer, D. F.; Tobias, P. E.; Ind. Eng. Chem. 34, 690 (1942).

System Components:

Potassium formate, $\ce{ KCHO2 }$; [590-29-4] NIST WebBook
Formic acid, $\ce{ CH2O2 }$; [64-18-6] NIST WebBook
Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook

Experimental Data

Note: The data for 323.2 K are given only in graphical form.

100w₁	100w₂	100w₃	$100 x_{1}$	$100 x_{2}$	$100 x_{3}$	Phase (s) () ^b
27.9	72.0	0.1	17.4^a	82.3^a	0.3^a	A
40.5	56.7	2.8	25.8^a	65.9^a	8.3^a	A
40.5	43.4	16.1	20.8^a	43.7^a	38.6^a	A
37.6	40.8	21.6	17.7^a	35.0^a	47.3^a	A
34.6	34.0	31.4	14.2^a	25.5^a	60.2^a	A
44.8	27.2	28.0	19.9^a	22.1^a	58.0^a	A
45.4	24.6	30.0	19.7^a	19.5^a	60.8^a	A
56.5	13.85	29.65	25.7^a	11.5^a	62.9^a	B
60.7	10.3	29.0	28.2^a	8.76^a	63.0^a	B
76.2	3.85	19.95	43.2^a	3.99^a	52.8^a	C
78.4	0.0	21.6	43.7^a	0.0^a	56.3^a	C

(a) These values were calculated by the compiler.

(b) The solid phases are: A = KCHO₂·CH₂O2; B = KCHO₂·CH₂O₂·0.5H₂O; C = KCHO₂.

IUPAC-NIST Solubility Data Series, SRD 106