SDS Volume
Volume 73. Metal and Ammonium Formate Systems, p None
Source Publication
Kendall, J.; Adler, H.; J. Am. Chem. Soc. 43, 1470 (1921).
Conditions:
Room Temp: 239.4 - 390.5 $\pu{K}$
Compiler:
Methodology:
The only information given is that the solubility values were determined by the freezing point method.
Sample Information:
- The ammonium salt was prepared by passing $\ce{NH3}$ into 90% formic acid. The product was recrystallized from absolute alcohol and dried over 99% sulfuric acid in a vacuum; MP = $\pu{390.5 \pm 0.2 K}$. The formic acid was prepared by treating a c.p. product with $\ce{B2O3}$. It was then distilled in vacuo until a product melting above $\pu{281.6 K}$ was obtained.
Measurement Errors:
Ambient temperature: Nothing is specified.
Mass concentration (m/v) (1): Nothing is specified.
System Components:
- Ammonium formate, $\ce{ NH4CHO2 }$; [540-69-2] NIST WebBook
- Formic acid, $\ce{ CH2O2 }$; [64-18-6] NIST WebBook
Experimental Data
| $100 x_{1}$ | $T_{\rm{unstab}}^{\rm{equ}}$ (°C) b | $T_{\rm{stab}}^{\rm{equ}}$ (°C) c | Phase (s) () a |
|---|---|---|---|
| 23.33 | -32.5 | - | D |
| 24.83 | -26.0 | - | D |
| 25.41 | -23.5 | - | D |
| 26.64 | -18.7 | -13.7 | D |
| 27.90 | -14.0 | -8.7 | D |
| 30.11 | - | 0.7 | D |
| 33.25 | 1.3 | 10.4 | D |
| 36.29 | 7.4 | 17.3 | D |
| 39.30 | 11.3 | 22.2 | D |
| 41.90 | 13.8 | 24.9 | D |
| 42.94 | 14.3 | 25.8 | D |
| 44.38 | - | D | 15.0 |
(a) Calculated by compiler assuming a linear function of $H_{\ce{C2H4}}$ vs $x_{\ce{C2H4}}$, i.e., $x_{\ce{C2H4}} (\pu{1 atm}) = 1/H_{\ce{C2H4}}$.
(a) The solid phases are: A = CH2O2; B = NH4CHO2·3CH2O2; C = NH4CHO2; D = NH4CH2O2·CH2O2.
(b) Denotes equilibrium temperature for unstable NH4CHO2.
(c) Denotes equilibrium temperature for stable NH4CHO2.
