Full text
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| Author(s): |
Fernanda Tomé Braz
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) |
| Defense date: | 2002-07-26 |
| Examining board members: |
Roberto Tokoro;
Queenie Siu Hang Chui;
Jorge Cesar Masini
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| Advisor: | Roberto Tokoro |
| Abstract | |
The solubility constant of the silver azide, AgN3, was determined through its solubility in water. The concentration of silver was determined by a saturated solution of silver azide at 25 ºC with the Flame Atomic Absorption Spectrometer having a value of (2,7 ± 0,2) x 10-5mol L-1 with 95% of confidence. The concentration of silver was determined also by Potenciometric technical with an electrode of metallic silver previously treated with a saturated solution diluted of silver azide and the solubility obtained was (2,43 ± 0,09) x 10-5mol L-1 with 95% of confidence. The solubility constant calculated by the equation Ks = (solubility)2 were (7,3±0,1)x10-10 mol2 L-2 by FAAS and (5,9±0,1)x10-10 mol2L-2 by Potenciometry. These values of solubility constants are connected with the size of the precipitate of the (27 ± 2) µm. The hidrolisys degree of the anion azide was determined trough the measuring of pH of pure water and pH after the saturation of water with the precipitate of silver azide. The variation was determined was (1,2 ± 0,6) x 10-7mol L-1 in terms of the concentration of hydroxyl liberated trough the protonation of azide. This value was lower than the uncertainty associated with the solubility of AgN3. In this way it was not taken in account (<0,5%). (AU) | |