SDS Volume (4745)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Sokolov, N. M.; Zh. Obshch. Khim. 24, 1581-93 (1954).
Variables:
Prepared by:
Method/Apparatus/Procedure:
A visual polythermal method was used. The melts were contained in glass tubes and stirred. The temperatures were measured with a Nichrome-Constantan thermocouple and a 17 mV full scale millivoltmeter. The temperature readings refer to the disappearance of isotropicity in the melt on cooling.
Source and Purity of Materials:
- The materials were prepared by reacting aqueous "chemically pure" sodium carbonate with a slight excess of the analytical grade proper acid. The solvent and excess acid were removed by heating to 160°C.
Estimated Errors:
Ambient temperature: The compiler estimates the accuracy of the temperature measurements to be probably ±2 K.
Mass concentration (m/v) (1): No information is given.
Components:
- Sodium formate, $\ce{ NaCHO2 }$; [141-53-7] NIST WebBook
- Sodium isobutanoate, $\ce{ NaC4H7O2 }$; [996-30-5] NIST WebBook
Experimental Data
Note: There are two eutectics: one at 252°C and 100 x2 = 1.3; the other at 250°C and 100 x2 = 96.5.
Melting temperatures for different mole fractions
| $T_{\rm{m}}$ ($\pu{K}$) | $T_{\rm{m}}$ (°C) | $100 x_{2}$ |
|---|---|---|
| 531 | 258 | 0 |
| 525 | 252 | 1.3 |
| 563 | 290 | 5 |
| 578 | 305 | 1E+1 |
| 587 | 314 | 15 |
| 592 | 319 | 2E+1 |
| 594 | 321 | 25 |
| 597 | 324 | 3E+1 |
| 599 | 326 | 35 |
| 600 | 327 | 4E+1 |
| 602 | 329 | 45 |
| 603 | 330 | 5E+1 |
| 602 | 329 | 55 |
| 600 | 327 | 6E+1 |
| 598 | 325 | 65 |
| 593 | 320 | 7E+1 |
| 587 | 314 | 75 |
| 579 | 306 | 8E+1 |
| 569 | 296 | 85 |
| 555 | 282 | 9E+1 |
| 531 | 258 | 95 |
| 523 | 250 | 96.5 |
| 533 | 260 | 1E+2 |
(a) The T/K values were calculated the compiler.
