Studies of the binding between elements and ascorbic acid using differential pulse polarography

Other Title(s)

دراسة ارتباط بعض العناصر مع حامض الاسكوربيك باستخدام البولاروغرافي النبض التفاضلي

Dissertant

Husayn, Muhammad Abd al-Khaliq

Thesis advisor

al-Rufai, Ilham M.

University

University of Baghdad

Faculty

College of Science

Department

Chemistry Department

University Country

Iraq

Degree

Master

Degree Date

2014

English Abstract

Chapter-one : Is a general introduction to the importance of a polarographic technique and it’s application.

An introduction about ascorbic acid, the studied metal and the molecular binding.

 Chapter-two: Gives an information about the polarographic apparatus, the cell, electrodes used, and some technical points specific for it’s experimental work.

 Chapter-three:  Studies the optimum condition for the polarographic measurement, a pulse amplitude 50 mV, scan rate 10 mV.s-1 and 0.1M KCl as a supporting electrolyte.

 Determination of peak potential for the studied metal (-1.05V for Ni(II), -0.63V for Cd(II), -0.16V for Cu(II), -1.39V for Fe(II) and +0.03V for ascorbic acid), by the use of DPP and DC technique.

 Studies the interaction between concentration on peak current which were linear and obeys Ilkovic equation, that means the waves were diffusion controlled.

 The number of electrons involved in the reduction process at the surface of the electrodes were determined by plotting log i/(id-i) VS E obtained by the DC polarograms.

XVI  Verification of the complexation between metal ions (Ni(II),Cd(II), Cu(II) and Fe(II)) and ascorbic acid were carried out by recording the Dpp of the mixture of these ions with ascorbic acid.

 Study the kinetic of the reactions between metal(II)-ascorbic acid system, by determinate the rate constant(the first and second order rate constants), the half-time, and the activation energy, which was done by following the polarographic wave as a function of time.

 Study the kinetic parameters, such as the rate constant and the transfer coefficient, of the electrode reactions, and determined the reversible and irreversible electrode process by plotting log(i/(id-i)) verses E for the D.C polarographic wave.

Kinetic parameters (K0 fh, αn) were calculated by Meites & Israel’s method and Gaur & Bhargava’s method, then study the temperature effect on these parameters.

 Determined the thermodynamic parameters such as free energy change G, enthalpy change H, and entropy change S, for the interaction between metal(II)-ascorbic acid system.

Main Subjects

Chemistry

Topics

• Analytical chemistry

No. of Pages

115

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-599738