The effects of temperature on the first and second acid dissociation constants of 8-hydroquinoline (oxine) have been measured and the following thermodynamic values assigned to solutions of 0.1M strength. For the process,
H₂Ox⁺ ⇋ H⁺ + HOx
at 25°C., pK₁ = 5.103, ΔH = 5.7 kcal/mole, and ΔS° = -4 e.u. For the second acid dissociation constant,
HOx ⇋ H⁺ + Ox⁻
at 25°C., pK₂ = 9.76, ΔH = 6.3 kcal/mole, and ΔS° = -23 e.u. The values for the second acid dissociation constant agree with those previously published. The values for the first dissociation constant have not been previously determined but are consistent with the result expected for reactions of this charge and chemical type.
The partition of 8-hydroxyquinoline was determined as a function of temperature for the following systems: water-benzene, water-nitrobenzene, water-toluene, and water-chloroform. The pertinent thermodynamic values for the partitions are as follows:
a. Water-benzene: log P = 2.44; ΔH = -2.0 kcal/mole; ΔS° = 4.5 e.u.
b. Water-nitrobenzene: log P = 2.67; ΔH = -1.7 kcal/mole; ΔS° = 6.6 e.u.
c. Water-toluene: log P = 2.33; ΔH = -1.3 kcal/mole; ΔS° = 6.2 e.u.
d. Water-chloroform log P = 2.703 ΔH = -2.5 kcal/mole; ΔS° = 3.9 e.u.
The values obtained for the water-chloroform system agree well with tho literature and serve as a check on the rest of the data.
The effect of temperature on the overall extraction constant of nickel oxinate and ferric oxinate was measured for the system water-chloroform. The thermodynamic values found for the process
Me⁺ⁿ + nHOx ⇌ MeOx<sub>n</sub> + nH⁺
are the following at 25°C. and an ionic strength of 0.1M:
a. Nickel oxinate log Kₑ = -2.73; ΔH = -40.4 kcal/mole; ΔS° = -148 e.u.
b. Ferric oxinate log Kₑ = -3.97; ΔH = -14.1 kcal/mole; ΔS° = -29 e.u.
The effect of ionic strength on the partition of S-hydroxyquinoline between water and benzene was determined for four different uni-univalent salts: potassium chloride, sodium chloride, potassium nitrate and sodium perchlorate. The “salting out” of oxine observed is typical of non-electrolytes. / Doctor of Philosophy
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/88668 |
| Date | January 1965 |
| Creators | Lipschitz, Irving |
| Contributors | Chemistry |
| Publisher | Virginia Polytechnic Institute |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | en_US |
| Detected Language | English |
| Type | Dissertation, Text |
| Format | 138 leaves, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 20269157 |
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