| Autor: |
K.L. Churney, George T. Armstrong |
| Rok vydání: |
2019 |
| Předmět: |
|
| Zdroj: |
Journal of research of the National Bureau of Standards. Section A, Physics and chemistry. (5) |
| ISSN: |
0022-4332 |
| Popis: |
The heat of combustion of NBS Standard Sample 39i of benzoic acid under standard bomb conditions has been determined in terms of electrical units. A value of −26,434.0 J g(−1) was obtained. The total uncertainty in our determination is estimated to be ±3.3 J g(−1). The uncertainty due to random errors was 1.7 J g(−1) and is based on the appropriate factors for the Student t distribution at the 95 percent confidence limits for eleven determinations of the energy equivalent of the calorimeter and six determinations of the heat of combustion of benzoic acid. The principal systematic error, neglect of surface temperature correction for our calorimeter, has been assigned a value of ±2.6 J g(−1) until more reliable estimates of the correction can be made. Particular emphasis was placed on improving the precision of a calorimetric measurement over those previously obtained in this laboratory by the use of more sensitive auxiliary measuring equipment and more accurate procedures to evaluate the corrected temperature rise. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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