The observations on the anomalous behavior of urea and the comparison between urea and thiourea in aqueous solutions have been examined by volumetric and ultrasonic sound velocity techniques at different temperature (298.15, 303.15, 308.15, 313.15, 318.15 and 323.15 K), atmospheric pressure by using a high accuracy vibrating U-tube digital density and ultrasonic sound velocity analyzer. The apparent molar volume (φv) & apparent molar adiabatic compressibility (φk) have been calculated from experimental density and ultrasonic sound velocity data respectively and limiting apparent molar volume (φ0), limiting apparent molar adiabatic compressibility (φ k 0) have been evaluated from apparent molar volume vs. molality plot as intercept. Apparent molar expansibility (φE) was determined from apparent molar volume and hydration number (nH) from adiabatic compressibility. The results show very interesting information about strong solute-solvent & solute-solute interactions, and also elaborate the structure making or breaking behavior in the solution mixtures. keywords: Urea, Thiourea, Apparent molar volume, Expansibility, Sound velocity, Hydration number.

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Volumetric and Ultrasonic Velocity Studies of Urea and Thiourea in Aqueous Solution

Volume-related solvation and pair interaction parameters for dilute solutions of urea and tetramethylurea in ethylene glycol between 288.15 K and 328.15 K: A comparative analysis

Densities of urea (U) and tetramethylurea (TMU) solutions in formamide (FA) and water with a solute molality of up to ∼2 mol kg–1 were measured at T = 288.15, 298.15, 308.15, 318.15, and 328.15 K a...

Solutions of Urea and Tetramethylurea in Formamide and Water: A Comparative Analysis of Volume Characteristics and Solute–Solute Interaction Parameters at Temperatures from 288.15 to 328.15 K and Ambient Pressure

Kinetic studies on solvolysis of cinnamoyl chloride in aqueous acetone and acetonitrile with lesser water content shows an order 2.6 with respect to water and it is comparable to that of benzoyl chloride. The relatively greater enthalpy and lesser negative entropy of activation compared to benzoyl chloride favours an S N 2 mechanism for cinnamoyl chloride rather than addition elimination mechanism. A sharp increase in rate observed in presence of small amounts of DMSO is due to its, strong basic and hydrogen bonding character leading to the liberation of strong nucleophile OH-, relatively greater stabilization of transition state than intial state which lowers the enthalpy and free energy of activation, distruction and interpenetration into the solvation shell of water and its direct interaction with the substrate.

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Effect of Added Dimethyl Sulphoxide on the Solvolysis of Cinnamoyl Chloride in Aqueous Acetone and Acetonitrile

Interaction-related volumetric and some other properties of urea solutions in aqueous N-tetramethylglycoluril (the mebicar drug) at different temperatures and under the ambient pressure

The volumetric studies on the binary aqueous solutions of sodium dodecyl sulphate (SDS) and ternary SDS-amino acid-water systems have been carried out as a function of concentration and at 15, 20 , 25 , 30 , 35 , 40 , 45 and 50 ° C. In this study the variation of apparent molar volume (φν) of SDS was observed in the low concentration region. The limiting apparent molar volume (φ0 ν ) values of SDS in aqueous amino acid solutions are greater than those in water and increase with the concentration at all the studied temperatures. The greater φ 0 ν value in amino acid solution has been demonstrated strong ion-ion interactions in the ternary system. Apparent molar expansions (Φ E ) in aqueous solution and ternary SDS-amino acid-water systems are very sensitive to hydrophobic and hydrophilic solute-solute interactions. Expansibility, α and apparent molar expansion, Φ E reflect from the same structural alteration in the solutions. In our investigation, critical micelle concentration (c.m.c) of SDS at various SDS-amino acid-water systems also determined by apparent molar volume (φ ν ). Among various physical parameters, apparent molar volume, limiting apparent molar volume, Apparent molar expansion has been recognized as a quantity that is sensitive to structural changes occurring in solutions.

http://www.orientjchem.org/pds/OJCV028I01P165-187.pdf

Volumetric Studies of Sodium Dodecyl Sulphate in Aqueous and Aqueous Amino Acid Solutions

/pdf/a-comparative-photocatalytic-activity-of-linbo3-and-tio2-by-1sqxpkqczu.pdf

A Comparative Photocatalytic Activity of LiNbO3 and TiO2 by Investigating the Removal Efficiency of Toluene from Indoor Air

Molecular Interactions and Aggregation Behavior of Cloxacillin Sodium in Water and Aqueous NaCl Solutions through Volumetric and Ultrasonic Sound Velocity Studies at 298.15 KMolecular Interactions and Aggregation Behavior of Cloxacillin Sodium in Water and Aqueous NaCl Solutions through Volumetric and Ultrasonic Sound Velocity Studies at 298.15 K

Roksana Khatun

Papers

Volumetric and Ultrasonic Velocity Studies of Urea and Thiourea in Aqueous Solution

Volumetric Studies of Sodium Dodecyl Sulphate in Aqueous and Aqueous Amino Acid Solutions

A Comparative Photocatalytic Activity of LiNbO3 and TiO2 by Investigating the Removal Efficiency of Toluene from Indoor Air