# CHIMICA ANALITICA I E LABORATORIO A - L

12 CFU - 1° Semester

### Teaching Staff

GIUSEPPE ARENA
Email: garena@unict.it
Office: Edificio 1, Cittadella universitaria, Viale A. Doria, 6, 95125 Catania
Phone: 095 738 5071
Office Hours: Tutti i giorni dalle ore 9 alle ore 19. Si prega solo di accertarsi che il docente non abbia altri impegni istituzionali.

## Learning Objectives

• MODULO 1

To enable students to become conversant with issues concerning equilibria in solution (acid-base, precipitation, complexation, redox).

Concepts acquired from this Module will then be used in the Laboratory Module.

• MODULO 2

To enable students to use autonomously the concepts acquired during the theoretical course (Module 1).

## Course Structure

• MODULO 1

Lectures associated to the analysis of numerical problems. Problems are presented and illustrated by the teacher and sometimes by the students themselves upon request.

• MODULO 2

Lectures associated to the analysis of numerical problems. Problems are presented and illustrated by the teacher and sometimes by the students themselves upon request.

## Detailed Course Content

• MODULO 1

Aim of the Course. Classification of the methods of analysis. Concentration units. Numerical examples.

Solution Equilibria. General principles. Gibbs energy and equilibrium constants. Factors influencing equilibrium constants; temperature, solvent, ionic strength. Activity and activity coefficients. Debye-Huckel's Law. Numerical examples. Acid-base equilibria. Strength of an acid. Mass, charge and proton balance equations. pH. Rigorous definition. Calculation of the pH of strong acids: rigorous equation and approximations. Approximation criterion. Numerical examples. Weak acids/bases. Calculation of the pH of weak bases: rigorous equation and approximations. Numerical examples. Mono- and two-color indicators: rigorous equations. Numerical examples.

Polyprotic acids: rigorous and approximate equations. Acid mixtures. Ampholytes. Distribution diagrams. Titration curves. Strong base with a strong acid, weak acid with a strong base, polyprotic acids. Numerical examples. Buffer solutions. Buffering capacity: rigorous equation. Numerical examples.

Precipitation equilibria. Solubility and solubility product. Factors influencing electrolyte solubility: temperature, solvent and ionic strength. Effect of a common ion, pH and formation of complexes. Titrations based on the formation of a precipitate. Error at the end point: rigorous equation. Numerical examples.

Complexation equilibria. Degree of formation. pH effect on complexation equilibria. Conditional constant. Metallochromic indicators. Choice of operational conditions. Complexometric titrations. Numerical examples.

Data treatment: outline. Experimental errors. Bias and random errors. Precision and accuracy. Sampling. Sample description. Position and dispersion parameters. Binomial distribution, Poisson distribution, normal distribution. Reduced normal. Main tests (Student test, F-test, χ2, Dixon’s test). Significant figure. Error propagation. Numerical examples.

This Module requires approximately 48 hrs, while the second Module requires 72 hrs; the total working time goes up since Students often ask for extra time for exercises outside the scheduled hours.

Please note: All the above arguments are deemed indispensable.

• MODULO 2

Laboratory. Choice of the analytical method. Instrumentation, precision, sensitivity. Result report.

Gravimetric analysis. Analysis through precipitation. Precipitate formation. Nickel determination by DMG.

Titrations: general principles. Preparation of standard solutions. Primary standards. Standardization procedure.

Acid-Base titrations. Na2B4O7.10H2O in acidimetric titrations. Determination of the titre of acids/bases commonly employed in a laboratory.

Precipitation titrations. Argentometry. Chloride determination according to Mohr and Fajans. Chloride/Carbonate separation

Complexometric titrations. EDTA titrations. Determination of Cu2+.

Redox titrations. Permanganometry. Determination of Fe2+ and H2O2. Iodometry. Determination of Cu2+.

This Module is expected to last for 72hrs. This does not include exercises upon student request, provided only if a facility is available.

## Textbook Information

• MODULO 1

1. Kolthoff, Sandell, Meehan e Bruckenstein - Analisi Chimica Quantitativa. Vol. 1 e Vol. 2, Piccin Editore.

2. E. De Simoni - Chimica Analitica, CUL (Bologna).

3. Skoog & West - Chimica Analitica. S.E.S.

4. D. H. Harris - Chimica Analitica quantitativa, Zanichelli.

5. Freiser e Fernando - Gli equilibri ionici della Chimica Analitica. Piccin Editore.

6. J. N. Butler - Ionic Equilibrium: Solubility and pH Calculations, Wiley

• MODULO 2

Kolthoff, Sandell, Meehan e Bruckenstein - Analisi Chimica Quantitativa. Vol. 1 e Vol. 2, Piccin Editore.

Vogel - Analisi Chimica Quantitativa. Vol. 1 e Vol. 2, J. H. Jeffery, J. Bassett, J. Mendham, R. C. Denney Editori, CEA

Freiser e Fernando - Gli equilibri ionici della Chimica Analitica. Piccin Editore.

Slides provided by the lecturer

Open in PDF format Versione in italiano