V. S. Rangra

Dielectric relaxation studies of binary mixtures of N-methylacetamide and acetonitrile in benzene solutions using microwave absorption studies

Abstract This paper is concerned with the dielectric relaxation times (τ) and the dipole moments (μ) of the binary mixtures of different molar concentrations of acetonitrile (CH3CN) in the binary mixtures of N-Methylacetamide (NMA) and acetonitrile (CH3CN) in benzene solutions. The physical parameters τ and μ have been calculated by using standard standing wave microwave techniques and Gopala Krishna’s single frequency (9.90 GHz) concentration variational method at different temperatures (25 °C, 30 °C, 35 °C, 40 °C). The dielectric relaxation process have been found to be an activated process. The energy parameters (ΔH, ΔF, ΔS) for the dielectric relaxation process of binary mixtures containing 30% mole-fraction of CH3CN have been calculated at the respective given temperatures and a comparison has been made with the corresponding energy parameters (ΔHη, ΔFη, ΔSη) for the viscous flow. On the basis of the observations, it is found that the dielectric relaxation process can be treated as the rate process like the viscous flow process. Solute–solute and solute–solvent molecular associations have been predicted.

Molecular Association between N‐methylacetamide and Dimethylsulphoxide Using Dielectric Relaxation Measurements in the Microwave Region

The dielectric relaxation times(τ) and the dipole moments(μ) of the binary mixtures of different molar concentrations of dimethylsulphoxide(DMSO) in the binary mixtures of N‐methylacetamide(NMA) and dimethylsulphoxide(DMSO) in benzene solutions have been calculated by using standard standing wave microwave techniques and Gopala Krishna’s single frequency(9.90GHz) concentration variational method at 25u2009°C. The solute‐solute and solute‐solvent type of the molecular associations has been predicted.

Dielectric Relaxation Study of Ethanol in Benzene from Microwave Absorption Data

The dielectric constant (ε’) and dielectric loss (ε″) of dilute solutions of ethanol in benzene have been measured at 9.883 GHz at 25, 30, 35 and 40 °C using standard microwave techniques. The dielectric relaxation time (τ) and dipole moment (μ) at 25, 30, 35 and 40 °C have been calculated by using the single frequency concentration variation method suggested by Gopala Krishna. It is found that the dielectric relaxation process can be treated as a rate process like the viscous flow process. A monomer structure of C2H5OH in benzene solution has been inferred. Based upon these studies, the presence of solute-solvent associations has been proposed. The energy parameters for the dielectric relaxation process have been calculated and compared with the corresponding energy parameters of viscous flow.

Dielectric relaxation studies of binary mixtures of N-methylacetamide and N-methylformamide in benzene solutions using microwave absorption data

Using standard microwave X-band technique and by following Gopala Krishnas single frequency (9.90u2009GHz) concentration variational method, the dielectric relaxation times (τ) and the dipole moments (μ) of dilute solution of N-methylacetamide (NMA), N-methylformamide (NMF) and NMAu2009+u2009NMF binary mixtures in benzene solutions have been calculated at different temperatures. The energy parameters for the dielectric relaxation process for NMAu2009+u2009NMF binary mixture containing 30u2009mol% NMF have been calculated at 25, 30, 35 and 40°C and compared with the corresponding viscosity parameters. A good agreement between the free energy of activation from these two sets of values shows that the dielectric relaxation process like the viscous flow process can be treated as the rate process. From relaxation time behavior of NMA and NMF binary mixture in benzene solution, solute–solute types of the molecular association has been proposed.

Dielectric Relaxation of Binary Mixtures of Tetrahydrofuran and N-Methylformamide in Benzene Solution Using Microwave Absorption Studies

Abstract Using standard standing wave microwave X-band technique and following Gopala Krishna’s single frequency (9.90 GHz) concentration variational method, the dielectric relaxation times τ and the dipole moments μ of dilute solutions of Tetrahydrofuran (THF), N-methylformamide (NMF), and THF+NMF binary mixtures in benzene solutions have been calculated at different temperatures (25°C, 30°C, 35°C, and 40°C). The energy parameters (ΔHε , ΔFε , ΔSε ) for the dielectric relaxation process for the THF+NMF binary mixture containing 30 mol% THF have been calculated at 25°C, 30°C, 35°C, and 40°C and compared with the corresponding viscosity parameters. A good agreement between the free energy of activation from these two sets of values shows that the dielectric relaxation process like the viscous flow process can be treated as a rate process. From relaxation time behaviour of THF and NMF binary mixture in benzene solution, solute-solute types of the molecular association has been proposed.

Dielectric Relaxation Studies of Mixtures of N-Methylacetamide and Ethanol in Benzene Solutions Using Microwave Absorption Technique

Using standard standing wave microwave X-band techniques, and by following Gopala Krishna’s single frequency (9.90 GHz) concentration variational method, the dielectric relaxation times (τ) and dipole moments (μ) of binary mixtures of different molar concentrations of ethanol (EtOH) in binary mixtures of N-methylacetamide (NMA) and ethanol in benzene solutions at 25, 30, 35 and 40 ◦C have been calculated. The activation parameters (ΔHε , ΔFε , ΔSε ) for the dielectric relaxation process of binary mixtures containing 30 mol% of EtOH have been calculated at 25, 30, 35 and 40 ◦C and compared with the corresponding viscosity parameters. A good agreement between the free energy of activation from these two sets of values shows that the dielectric relaxation process, like the viscous flow, can be treated as a rate process. From relaxation time behaviour of NMA and EtOH binary mixtures in benzene solution, solute-solute and solute-solvent types of the molecular association have been predicted.

Dielectric relaxation studies of binary mixtures of ethyl alcohol and tetramethylurea in the benzene solution from microwave absorption data

Summary The dielectric relaxation studies of different molar concentrations of ethanol (C2H5OH) in the binary mixtures of ethanol and tetramethylurea in benzene solutions have been studied at 9.883 GHz by using standard standing microwave techniques and Gopala Krishna’s single frequency concentration variation method at different temperatures (25°C, 30°C, 35°C and 40°C). It is found that dielectric relaxation time varies non-linearly with the variation in molar concentration of ethanol in the whole concentration range of the binary mixture. Based upon above results solute–solute and solute–solvent types of molecular association have been proposed. The dielectric relaxation process for 50% mole fraction of ethanol in the binary mixture is found to be an activated process. The energy parameters (ΔHε, ΔFε, ΔSε) for the dielectric relaxation process of binary mixtures containing 50% mole fraction of ethanol have been calculated at the respective given temperatures. Comparison has been made with the corresponding energy parameters for viscous flow process. It is found that the dielectric relaxation process can be treated as the rate process like the viscous flow process.

Dielectric Relaxation of Mixtures of N-Methylacetamide and N,N-Dimethylformamide Solved in Benzene Using Microwave Absorption Data

The dielectric relaxation times τ and dipole moments μ of N-methylacetamide (NMA) mixed with N,N-dimethylformamide (DMF) in benzene solutions have been obtained using standard standing wave microwave techniques and Gopala Krishna’s single frequency (9.90 GHz) concentration variational method at 25, 30, 35, and 40 ◦C. The energy parameters (ΔHε , ΔFε , ΔSε ) for the dielectric relaxation process of mixtures with equal amounts of NMA and DMF have been calculated and compared with the corresponding energy parameters (ΔHη , ΔFη , ΔSη ) for the viscous flow. On the basis of the observations it is found that the dielectric relaxation process can be treated as a rate process like the viscous flow. Solute-solute and solute-solvent types of the molecular associations have been predicted