Viscosities of some tetraalkylammonium bromides in 2-ethoxyethanol at 308.15, 313.15, 318.15, and 323.15 K

2005 ◽  
Vol 83 (5) ◽  
pp. 499-504 ◽  
Author(s):  
Purushottam Haldar ◽  
Bijan Das

The viscosities of the solutions of tetraethylammonium bromide (Et4NBr), tetrapropylammonium bromide (Pr4NBr), tetrabutylammonium bromide (Bu4NBr), tetrapentylammonium bromide (Pen4NBr), and tetraheptylammonium bromide (Hep4NBr) in 2-ethoxyethanol have been reported at 308.15, 313.15, 318.15, and 323.15 K. The viscosity data have been analyzed by the Jones–Dole equation for the associated electrolytes to evaluate the viscosity B coefficients of the electrolytes. These data have also been analyzed by the transition-state treatment to obtain the contribution of the solutes to the free energy of activation for viscous flow of the solution. The viscosity of the solvent is found to be greatly modified by the presence of all of the tetraalkylammonium ions investigated. Moreover, the tetraalkylammonium ions are found to be unsolvated in 2-ethoxyethanol solutions, they behave neither as structure-breaker nor as structure-maker and the formation of the transition state is made less favorable in their presence.Key words: viscosity, electrolytes, tetraalkylammonium ion, 2-ethoxyethanol, ionic contribution, solvation, transition-state treatment.

2004 ◽  
Vol 59 (9) ◽  
pp. 615-620 ◽  
Author(s):  
Dip Singh Gill ◽  
Hardeep Anand ◽  
J. K. Puri

Viscosity and molar conductance of Bu4NBPh4, Bu4NClO4, [Cu(CH3CN)4]ClO4, NaClO4 and NaBPh4 have been measured in the concentration ranges 0.02 - 0.5 mol dm−3 and 0.0005 - 0.0065 mol dm−3 at 298.15 K in AN + DMF mixtures containing 0, 10, 20, 40, 60, 75, 80, 90, and 100 mol % DMF. The viscosity data have been analyzed by the extended form of the Jones-Dole equation in the form: (η/η0) = 1+AC1/2+BC+DC2 to evaluate B and D parameters and the conductance data by the Shedlovsky equation to evaluate Λo and KA values of the salts. Ionic viscosity B-coefficients (B±) and ionic molar conductances (λ◦ i) have been calculated by using Bu4NBPh4 as a reference electrolyte. Solvated radii (ri) for Na+, Cu+ and ClO4 − have been estimated by using Gill’s modification of Stokes’ law. The variation of B± and ri as a function of mol % DMF shows that both Na+ and Cu+ are highly solvated in AN + DMF mixtures over the entire composition region. The solvation passes through a maximum between 40 to 80 mol % DMF. Both Na+ and Cu+ are more strongly solvated between 40 to 80 mol % DMF. Cu+ is relatively more strongly solvated than Na+ in AN + DMF mixtures. ClO4 − shows poor solvation in AN + DMF mixtures.


2019 ◽  
Vol 233 (2) ◽  
pp. 167-182 ◽  
Author(s):  
Anwar Ali ◽  
Nizamul Haque Ansari ◽  
Ummer Farooq ◽  
Shadma Tasneem ◽  
Firdosa Nabi

Abstract The densities, ρ, viscosities, η and specific conductivities κ, of (0.0002, 0.0004, 0.0006 and 0.0008 m) CTAB in 0.1 m aqueous valine, leucine and isoleucine were measured at different temperatures. The measured data were used to calculate various useful thermodynamic parameters. A complete characterization of any mixture can be performed by means of these thermodynamic properties. The apparent molar volume, ϕv, partial molar volume, $\phi _v^0$ and partial molar isobaric expansibilities, $\phi _E^0,$ were calculated using density data. The viscosity data were analyzed using Jones–Dole equation to obtain viscosity coefficients, A- and B-, free energy of activation per mole of solvent, Δμ1°∗, and solute, Δμ2°∗, enthalpy, ΔH∗ and entropy, ΔS∗ of activation of viscous flow. Measuring the changes in these properties has been found to be an excellent qualitative and quantitative way to obtain information regarding the molecular structure and intermolecular interactions occurring in these mixtures. Various structure-making/breaking ability of solute (cetyltrimethylammonium bromide) in presence of aqueous amino acid solutions were discussed. In addition, fluorescence study using pyrene as a photophysical probe has been carried out, the results of which support the conclusions obtained from other techniques.


1993 ◽  
Vol 46 (11) ◽  
pp. 1673 ◽  
Author(s):  
LT Byrne ◽  
JM Harrowfield ◽  
DCR Hockless ◽  
BJ Peachey ◽  
BW Skelton ◽  
...  

The hydroxide ion catalysed phosphorylation of p-t- butylcalix [4] arene by diethyl chlorophosphate under heterogeneous conditions shows a marked sensitivity to the nature of the phase transfer catalyst used. Thus, substitution of tetraethylammonium bromide for the tetrabutylammonium bromide prescribed for the synthesis of the calixarene tetraphosphate leads to a major reaction product becoming a bis (phosphate) in which the calixarene binds as a unidentate ligand to one phosphorus and as a bidentate ligand to the other. An X-ray crystal structure analysis on this new compound shows the calixarene to adopt a somewhat distorted 'cone' conformation with an unusual orientation of one of the t-butyl substituents into the cone cavity. It also reveals that a significant diastereoselectivity must operate in the formation reaction. The only other reaction product detected in this system appears to be the calixarene tetraphosphate in a partial cone conformation.


2020 ◽  
Vol 10 (01) ◽  
pp. 170-174 ◽  
Author(s):  
Sundus H. Merza ◽  
Nagham H. Abood ◽  
Ahamed M. Abbas

The interactions of drug amoxicillin with maltose or galactose solutions with a variation of temperature have been discussed by taking in the volumetric and viscometric procedures. Physical properties [densities (ρ) and viscosities (η)] of amoxicillin (AMOX) aqueous solutions and aqueous solutions of two type saccharides (maltose and galactose 0.05m) have been measured at T = (298.15, 303.15 and 308.15) K under atmospheric pressure. The apparent molar volume (ϕv cm3mole-1) has been evaluated from density data and fitted to a Redlich-Mayer equation. The empirical parameters of the Mayer-Redlich equation and apparent molar volume at infinite dilution ذv were explicated in terms of interactions from type solute-solvent and solute–solute interactions. Transfer molar volume Δtraذv for AMOX from water to aqueous maltose and galactose solutions were calculated to comprehend different interactions in the ternary solutions. Limiting apparent molar expansibility (ذE) and Hepler’s coefficient was also calculated to indicate the structure making ability of AMOX in the ternary solutions. Jones–Dole coefficient B and A have been calculated from viscosity data by employing the Jones–Dole equation. The free energy of activation of viscous flow per mole of the solute (Δμ°2*) and solvent (Δμ°1*) have been explained on the basis of the Eyring and Feakins equation.


1985 ◽  
Vol 63 (6) ◽  
pp. 1180-1184 ◽  
Author(s):  
Anil K. Puri

Partial molar volume [Formula: see text] partial molar compressibility [Formula: see text] Jones–Dole viscosity B coefficient, and solute activation parameters of adenosine in water–DMSO mixtures in the presence of Ca2+ and K+ ions have been calculated from ultrasonic, volumetric, and viscometric studies at 25, 30, 35, and 40 °C(± 0.01° C). The results are discussed in terms of the Jones–Dole viscosity B coefficients and the transition state parameters for viscous flow.


2019 ◽  
Vol 31 (11) ◽  
pp. 2557-2566
Author(s):  
Shashi Kant Sharma ◽  
Poonam ◽  
Nisha Sharma

To investigate the behaviour of doxycycline hyclate in water, aqueous glycine and aqueous L-alanine solutions, the viscometric and conductometric studies have been conducted at different temperatures. Viscosity data has been used to derive the Jones-Dole viscosity B-coefficient, temperature derivative of B-coefficient (dB/dT), viscosity B-coefficient of transfer (ΔtrB), free energy of activation of viscous flow per mole of solvent (Δμ1 o*) and solute (Δμ2o*) respectively, activation entropy (ΔS2o*) and activation enthalpy (ΔH2o*). Conductance data has been used to compute Walden product (Λm oηo) and temperature coefficient of Walden product (dΛmoηo/dT) for doxycycline hyclate in water, and in aqueous glycine and aqueous L-alanine solution. The positive values of B-coefficient, ΔtrB indicate the prevailing of hydrophilic-ionic interactions in the systems under examination. The negative values of dB/dT and positive values of temperature coefficient of Walden product infer structure maker tendency of doxycycline hyclate in water, and in aqueous glycine and aqueous L-alanine solution. Transfer energy parameters indicate the breaking of intermolecular bonds in transition state which means that formation of activated complex is unfavourable


Atmosphere ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 665 ◽  
Author(s):  
Attoui ◽  
Kangasluoma

Tetraheptylammonium bromide (THABr), tetrabutylammonium bromide (TBABr) and tetraethylammonium bromide (TEABr) dissolved in methanol or water methanol mixtures (~ 1mM) produce via positive electrospray atomization and high resolution classification electrical classification standard clean ions (monomer and dimer) which are singly charged. THABr is hydrophobic and insoluble in water, TBABr and TEABr are hygroscopic and water soluble (0.6 and 2.8 kg/l respectively). These ions are used to study the effect of hygroscopicity on the activation of aerosol particles in the sub 2 nm range via the detection efficiency measurement of a boosted ultrafine TSI condensation particle counter (3025A). Water solubility of particles seems to play a role in the activation and growth with butanol vapor in the CPC (condensation particle counter) independently of the size.


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