Ultrasonic Study and Properties of Molecular Interactions in Binary Liquid Mixture of Dibutylamine with Methanol

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1 Ultrasonic Study and Properties of Molecular Interactions in Binary Liquid Mixture of Dibutylamine with Methanol V.V.Hari Babu* 1, M.V.K.Mehar 2 *1Assistant Professor, Dept.ofPhysics, Bapatla Engineering college, Bapatla,Guntur Dt., A.P.,India vvharibabu@gmail.com 2Lecturer in Physics, GDC, Alamuru, E.G.Dt.,A.PState, India mamatikrishnamehar@gmail.com Abstact:Ultrasonic study of Binary liquid mixture of Dibutylamine with Methanol at different molefractions (X 1 and X 2 ) were studied and found various parameters at the temperature 303 K. Ultrasonic Interferometer were used to find out ultrasonic velocity at 2MHz with special designed double walled quartz crystal.ultrasonic velocity,viscosity,adiabatic, density, compressibility, molar valume and intermolecular free length were calculated. Some excess parameters like excess viscosity, excess adiabatic compressibility,excess molar volume and excess intermolecular free length were calculated theoretically. It is observed that Ultrasonic velocity increases with increasing mole fraction DBA(X 1) and increases velocity with decreasing mole fraction MEOH(X 2) similarly Molar volume,density and viscosity follows the same trend. Inter molecular free length and diabatic compressibility shows similar behavior i.e both are decreases for X 1 upto0.488 and X 2upto0.512 then slightly increases with further decreasing X 1 and increasing with X 2.Excess adiabatic compressibility obtained the negative values which are decreases with increasing X 1 upto while decreases with X 2 upto0.737 then increases with further increases X 1 and decreasing withx 2 except pure liquids. In case of Excess intermolecular free length obtained negative values which are decreases with increasing X 1upto while X 2 decreases upto then increases with increases with further increasing X 1 and decreasing X 2 except pure liquids. Excess molar volume obtained the negative values which are decreases with increasing X 1upto and with decreases X 2upto then excess intermolecular freelength slightly increases with further increasing X 1 and decreasing X 2 except pure liquids.excess viscosity increases with increasing X 1 upto and decreasing X 2upto then excess viscosity slightly decreases with further increases X 1 and decreases X 2 except pure liquids. Keywords: Ultrasonic velocity, Excess parameters, Binary liquids, Intermolecular, Interactions, Thermodynamic \ Properties 1. INTRODUCTION Ultrasonic Properties are still key role to know and investigate certain physical, chemical and thermo dynamical properties of the materials or liquids.various parameters obtained from ultrasonic velocity in liquid mixtures and solutions, and other parameters like attenuation, acoustic impedance etc. and their variation with concentrations helps to understand the nature of molecular interactions in the mixtures.concentrationvariation of solvents in liquid mixtures have significant properties need to technological applications and it reveals the more information about the liquid state. Ultrasonic properties explains interrelated properties in liquids combining or individually. The investigation of propagation of ultrasonic waves in liquids and liquid Mixtures provide amore information on the nature of the inter molecular and intra molecular interactions in these liquid systems. The study [1-4] and properties of ultrasonic velocity in liquids, liquid mixtures and their interpretation in the light of molecular structure has obtained much significant role during the last decades. Ultrasonic velocity and related parameters of liquid mixtures are found to be the most powerful tool to investigating and understanding the theoriesof the liquid state and toderive some useful properties of liquid mixtures which are not easily accessible by other means. 138

2 The indication of positive excess values says weak interactions and negative values says strong interactions between the components liquid.dibutylamine(dba) is used as a plasticizer in pvc materials. Polyurethane (PUR) Plastic, the production of pharmaceuticals. There are lots of applications as chemicals intermediates, e.g. corrosion inhibitors, food factory, emulsifiers, dyes, photographic chemicals, plasticizers, additives for fuels and lubricants, floatation agents, accelerators in the rubber chemical industry, catalysts, agricultural chemicals.ethanol (C 2 H 6 O) is widely used in numerous industrial, they have lot of application paints printing inks. A. REVIEW OF LITERATURE T. Sumathi[5] et al studied of ultrasonic velocity, density and viscosity measurement of methionine in aqueous electrolytic solutions at 303K, observed the results were discussed in terms of structure - making and structure breaking effect of amino acids in the mixtures[6,7]. The experimental results of ultrasonic velocity and theoretical result of ultrasonic velocities using nomoto[8]. The physical properties of amino acids in aqueous solution have been studied to understand solute-solvent interactions and their role in the stability of proteins discussed by Yan Z, et al [9]. A.S. Aswar and D.S. Choudhary [10] have measured the density, ultrasonic speed for 2-hydroxy-5-methyl-3- nitroacetophenone in N, N- dimethylformamide at four equidistant temperatures from K. Ultrasonic studies, densities and viscosities of binary liquid mixture of ethylamine and benzyl alcohol have been measured by C.M Saxena et.al [11] at different temperatures at 30ºC, 35ºC and 40ºC. The experimental value of speed of sound (U), isentropic compressibility (βs), intermolecular free length (L f ), viscosity (η), available volume (Va), molar volume (V) and Nissan s parameter (d) have been calculated of ethyl amine and benzyl alcohol in the pure state as well as mixture over whole composition range were measured at 30ºC, 35ºC and 40ºC. Zareena Begum et.al [12-14] studied thermo dynamic parameters such as excess molar volumes (ΔV) of binary mixtures of anisic aldehyde with some normal alkanols and alkoxy alcohols at various temperatures. Densities and ultrasonic speed have been measured by Sahu et.al [15] at 303K for the binary mixture of di acetone alcohol and Chlorobenzene over entire composition range. From these isentropic compressibility (K), intermolecular free length (L f), acoustic impedance (Z) and their deviations namely excess isentropic compressibility (Δβ), Excess intermolecular free length (ΔL f), acoustic impedance (Z) have been calculated and interpreted in terms of intermolecular interactions. II.EXPERIMENTAL DETAILS Various parameters of ultrasonic and thermodynamical properties like ultrasonic velocity (U), density (ρ) and viscosity (η), have been measured in mixtures of DBA(Dibutylamine) and MEOH (Dibutylamine with Ethanol) at 303K with mole fractions(x 1) and(x 2). Adiabatic compressibility (k s), molar volume (V),inter molecular free length(l f), excess intermolecular free length (ΔL f), excess viscosity (Δη), excess molar volume (ΔV) and excess adiabatic compressibility (Δk s) were also calculated theoretically. Ultrasonic velocity in liquids were measured using ultrasonic interferometer at 2 MHz frequency is a simple and direct device with high degree of accuracy. The principle used in this measurement is based on the determination of wavelength in the medium which is accurate. The known frequency of ultrasonic waves was produced by a crystal called quartz crystal which is placed at the bottom of the cell.the principle used in this measurement is based on the determination of accurate great length in the medium. The density of liquid mixtures of chemical solutions were measured by using 10 ml of specific gravity bottle measured by using following the formulae with maximum possible percentage error in density is less than 1%: ρ = gm/cm 3 (1) ρ = m/v where, ω 1 is the empty bottle weight, ω 2 is the binary mixture solution weight. 139

3 The viscosity liquid is measured by an Ostwald viscometer with using the relation is η 2 = η 1 ρ 2t 2 /ρ 1 t 1 m pas (2) A. Theoretical Calculations The experimentally measured ultrasonic velocity (U), viscosity (η) and density (ρ) are used to compute parameters like adiabatic compressibility (k), molar volume (V), intermolecular free length (L f), excess viscosity (Δη), excess compressibility (Δk), excess molar volume (ΔV) and excess intermolecular free length (ΔL f) by using following expressions discussion by Mehra& Rita (16) and Ali & Nain(17). L f = K (k s ) 1/2 (3) k s= 1/ρc 2 (4) V m = M eff /ρ (5) Δη = η (exp) - η (ideal) (6) ΔL f = L f (exp) - L f (ideal) (7) Δk s=k s (exp) - k s (ideal) (8) Δv = v (exp) - v (ideal) (9) Where, L f (ideal) is ideal mixing intermolecular free length. η (ideal) is ideal mixing viscosity. k s (ideal) is ideal mixing compressibility. V (ideal) is ideal mixing molar volume. M eff is molecular weight. K is the temperature dependent constant (Jacobson s constant). III. RESULTS AND DISCUSSION The ultrasonic velocity (U), viscosity (η) and density (ρ) have been measured in mixtures of DBA andmeoh at 303K. The values of ultrasonic velocity (U), density (ρ), viscosity (η), molar volume (V), adiabatic compressibility (k), inter molecular free length (L f), for mixture of various mole fractions of DBA are presented in Table-1. The values of excess intermolecular free length (ΔL f), excess viscosity (Δη), excess molar volume (ΔV) and excess adiabatic compressibility (Δk) are noted in the Table-2. In the present in study, it is investigated that the ultrasonic velocity increases with mole fraction of DBA and with decreasing mole fraction MEOH (Inverse proportionality relation) indicates the intermolecular interaction confirms the binary liquid mixture.from Fig.1 it is showsthat the variation of ultrasonic velocities in mole fractions due to the molecular interaction through structural arrangement of molecules in liquid mixture. When system attains a closure packing one would expect the corresponding structural changes to result in a increased ultrasonic velocity. The density of the samples were determined and noted in Table-1 which are slightly decreases with increasing molefractionx 1 and decreases with decreasing molefraction X 2.The decreasing density can be explained on the basis of molar volume. 140

4 TABLE 1 Values of Mole fraction of DBA( X 1 ), Mole fraction of MEOH (X 2 ), Density (ρ), Viscosity (η), Ultrasonic Velocity (U), Adiabatic compressibility (K), Inter molecular free length (L f ), Molar volume (V). Molefra ction X 1 Molefrac tion X 2 Density ρ (g/cm 3 ) Viscosity η (m pas) Ultrasonic Velocity U (cm/s) Adiabatic compressibility K (cm 2 /dyne) Inter molecular free length L f (cm) Molar Volume V (cm 3 ) E E E E E E E E E E E E E E E E E E E E E E E E E E

5 TABLE 2 Valuesofmole fractionof DBA (X) 1,Molefraction of MEOH(X 2),Excessadiabatic compressibility (Δk), Inter molecular excess free length (ΔL f), Excess molar volume (ΔV), Excess viscosity (Δη). X 1 X 2 ΔK (cm 2 /dyne) ΔL f cm ΔV cm 3 Δη m pas E E E E E E E E E E E E E E E E E E E E E E Ultrasonic Velocity:(m/sec) Molefraction(X 1 ). Fig 1: The Variation of viscosity with mole fraction of DBA 142

6 The variation of molar volume (V) with respect to mole fraction of DBA is shown in Fig 2. The dependence of excess molar volume on mole fraction of DBA is illustrated in Fig. 3. From Table-1 it is noticed that the molar volume of mole fraction X 1 increases with increasing molar volume due to increasing molar mass,converse to this molar fractionx 2 is decreases with increasing molar volume due to decreasing molar mass. The negativeexcess molar volumes are presented in Table-2 whichare decreases with increasing molefractionx 1upto0.488 and with decreasing X 2upto then after it is increases with further increasing X 1 and with decreasing X 2 except pure liquids. The negative values of excess molar volume (ΔV) for DBA and MEOH mixture may be the result of strong intermolecular interactions between DBA and MEOH molecules through formation of hydrogen bonding. The negative values of excess molar volume of binary mixtures of N,Ndiethylaniline with ketones may be attributed to the dipole dipole interactions resulting in the formation of electron transfer complexes between ketones and N,N-diethylaniline [18] Molar Volume:cm Molefraction(X 1 ) Fig.2: Variation of molar volume with mole fraction of DBA Molefraction(X1). Excess Molar Volume:cm Fig.3: Variation of excess molar volume with mole fraction of DBA 143

7 The viscosity of DBA and MEOH mole fractions were noted in Table-1 and observed that the viscosity increases with mole fraction X 1 and also increases with decreasing mole fraction X 2. The increasing and decreasing Viscosity explained on the basis of fluid resistance to flow to gradual deformation by shear stress. The high viscosity due to molecular make up gives the lot of internal friction, From Table-2 the excess viscosity values are increases with mole fraction X 1upto and also increases with decreasing mole fraction X 2 upto then it is decreases with increasing X 1 and with decreasing X 2 except pure liquids. The positive excess viscosity values indicate the existence of specific interactions between component molecules hence increases similarly molecular size decreases the magnitude of the excess viscosity decreases [19].The behavior of viscosity can understand by Fig.4 and excess viscosity behavior can understand through plotted graph between excess viscosity and DBA in Fig Viscosity:mpas Molefraction(X 1 ) Fig.4: Variation of viscosity with mole fraction of DBA Excess Viscosity:m pas Molefraction(X 1 ) Fig.5: Variation of excess viscosity with mole fraction of DBA From the Table-1 it observed that the adiabatic compressibility decreases upto with increasing X 1upto and with decreasing molefraction X 2 upto from where it is slightly increases with further increasing X 1 and with further decreasing X 2.Decreasing adiabatic compressibility due to molecules are a closer packing similarly increasing adiabatic compressibility due to not closely packed and there is some free space between the molecules for movement. The Fig.6 shows the behavior of adiabatic compressibility with mole fraction X

8 Adiabaticcompressibility:cm 2 /dyne 1.1E E-10 1E E-11 9E E-11 8E Molefraction:(X 1 ) Fig-6: Variation of adiabatic compressibility with mole fraction of DBA The excess adiabatic compressibility obtain the negative values are showing in Table-1 which are decreasing with increasing X 1upto0.263 and with decreasing X 2upto0.737 then again slightly increases with increasing mole fraction X 1 and with decreasing X 2. The adiabatic compressibility shows a reverse trend to that of ultrasonic velocity indicates closure packing of component molecules which confirms the decrease in free length. The negative values of excess adiabatic compressibility shows the confirmation of inter molecular association between the component molecules. Intermolecular free length is (L f ) is decreases with increasing molefraction X 1 upto0.488 and with decreasing mole fraction X 2 upto then increases with further increasing X 1 and with decreasing X 2 except pure liquids.the increase of intermolecular free length indicates weakening the intermolecular attraction and the decrease of L f indicates strengthening the intermolecular attraction. Excess intermolecular free length possessing negative values are showing in Table-1 which are decreases with increasing mole fraction X 1 upto0.263 and with decreasing X 2upto0.737 then increases with further increasing X 1 and with further decreasing X 2. According to Ramamurthy et al [20-21] negative values of excess intermolecular free length indicate that sound waves cover longer distances due to decrease in intermolecular free length describing the dominant nature of hydrogen bond interaction between unlike molecules. The excess intermolecular free length decreases for closely packed component molecules of the mixture which may be due the strong interaction between molecules of the binary mixture. A The behavior of excess adiabatic compressibility can be understand through plotted graph between molefraction X 1 and excess adiabatic compressibility in Fig.7. ExcessAdiabatic Compressibility:cm 2 /dyne 0-2E-12-4E-12-6E-12-8E-12-1E E E E E Molefraction(X ) Fig-7: Variation of excess adiabatic compressibility with mole fraction of DBA 145

9 IV. CONCLUSION Ultrasonic velocity with various thermo dynamical parameters of Binary Liquid Mixture of Dibutylamine with Methanol were studied systematically at temperature 303K. Ultrasonic Velocity of molefractions X 1 is shows proportionaterelationupto then showing inverse relation converse to this molefraction X 2 shows inverse relationupto 0.52 then exhibits the proportionate relation due to structural arrangements of molecules.density and molar volumes of molefraction X 1 and X 2 shows mutually inverse relation explained on the basis of molar and volume relation. Excess molar volume may be the reason of strong intermolecular interactions between DBA and MEOH molecules through formation of hydrogen bonding.adiabatic compressibility and Intermolecular free length are showing similar behaviouri.e.both are decreases with increasing molefractions X 1 upto then with further decreasing mole fractions X 2 upto from where both are increases with further increasing molefraction X 1 and with further decreasing mole fraction X 2 due to closely packed and not closely packed. The excess adiabatic compressibility and excess intermolecular free length are also behaves similarly i.e. both are decreases with increasing molefraction X 1 upto and with decreasing mole fraction X 2 upto then both are increases with further increasing X 1 and with further decreasing X 2. The negative values of excess adiabatic compressibility shows the confirmation of inter molecular association between the component molecules negative values of excess intermolecular free length indicate that sound waves cover longer distances due to decrease in intermolecular free length describing the dominant nature of hydrogen bond interaction between unlike molecules and packing of component molecules which confirms the decrease or increase in free length.viscosity is increaes with increasing molefraction X 1 exepect where slightly increased and with decreasing mole fraction X 2. The increasing and decreasing Viscosity is explained on the basis of fluid resistance to flow to gradual deformation by shear stress. Excess viscosity values are increases with mole fraction X 1upto and also increases with decreasing molefraction X 2upto then it is decreases with increasing X 1 and with decreasing X 2 except pure liquids. The positive excess viscosity values indicate the existence of specific interactions between component molecules hence increases similarly molecular size decreases the magnitude of the excess viscosity decreases. References [1] Syal V.K, Chauhan M.S, Chandra B.K& Chauhan S, Journal of pure and applied Ultrasonic, Vol.(18)1, pp.104, 1996 [2] Nikkam P.S, Pathak R.B &Hasan M, Journal of pure and applied Ultrasonic, Vol.(18)1, pp.19,1996. [3] Amalendupal and Guru Charandas,Journal of pure and Applied Ultrasonics, Vol. (21)1,pp. 9, 1999 [4] Nikkamps, Jdhav M. C and Hasan.M, Molecular-interactions in Mixtures of dimethylsulfoxide with some alkanols - an ultrasonic study, Acustica,Vol. (83)1, pp. 86,1997. [5]. Sumathi T, Priyatharsini S, PunithasriS,Indian J Pure&ApplPhys., Vol.(49),,pp.328, 2011 [6]. F.J.Millero,A.Surdo and Shinc,J.Phys.Chem.,Vol.(82)1,pp.,784,1978. [7]. R.Bhat and J. C Awuwalia,J.Phys.ChemVol.(.99),pp.,1099,1985. [8]. Nomoto O.,J.Phys.Soc.Jpn.Vol(13)1, pp ,1958 [9] Yan Z & Wang J Lu J, BiophysChem, Vol.(99)1,pp , 2002 [10] Aswar A.S. &Choudhary D.S., Bull. Chem. Soc. Ethiop., 27(1), 2013 pp 155. [11]Chandra Mohan Saxena, ArchnaSaxena, Ashok Kumar Srivastava & and Naveen Kumar Shukla, American Chemical Science J, Vol.(4)3, pp 468, 2013 [12] Zareena Begum, Sandhya Sri P.B., Karuna Kumar D.B., &Rambabu C., J of Mol. Liq. 178, 2013 pp 99. [13]Zareena Begum, Sandhya Sri P. B., &Rambabu C., ISRN Physical Chemistry, Article ID , 2012, [14] Zareena Begum, Sandhyasri P.B Karuna Kumar D.B., Rayapa Reddy K. &Rambabu C., J. Mol. Liquids,Vol.(184)1,pp 33,2013,. [15] SahuS.NathG.&PaikarayR.ResearchJournalofChemSci,vol.2(11), pp [16] Rita Mehra&MeenakshiPanchidi,Indian Journal of Pure and Applied Physics,Vol.(45),pp.5801, 2007 [17] AnilKumarNian,,Fluid Phase Equilibria,Vol.(259)1, pp.218,

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