# Analytical Chemistry II and Laboratory

**Academic Year 2023/2024**- Teacher:

**ROBERTA D'AGATA**

## Expected Learning Outcomes

## Course Structure

Class and laboratory experiments.

Should teaching be carried out in mixed mode or remotely, changes with respect to previous statements may be introduced, in line with the outlined syllabus.

According to safety requirements linked to the pandemic, learning assessments may also be carried out online.

## Required Prerequisites

## Detailed Course Content

1. Spectroscopy:

Electromagnetic radiation: wave-particle dualism, photoelectric effect and diffraction, Heisenberg's principle. Electromagnetic spectrum. Refraction, refractive index, Snell's law, total internal reflection. Interaction of radiation with matter: reflection, transmission/absorption, diffusion (Rayleigh, Mie, Raman). Absorption and emission of radiation. Atomic absorption. Molecular absorption. Vibrational and rotational motions. Fluorescence, phosphorescence.

2. Molecular spectroscopy - UV-vis

Transmittance, absorbance, Beer's law. Limitations of Beer's law. Photometer and spectrophotometer. Single beam spectrophotometer, Double beam spectrophotometer. Sources. Wavelength selectors. Transducers: photovoltaic cells, photocathodes, photomultiplier tubes, series of diodes, charge injection, coupled charge.

3. Molecular spectroscopy - infrared

General characteristics. Harmonic and anharmonic oscillator, dipolar moment of transition. Molecular vibrational modes. Main IR signals: functional groups area, fingerprint area. Dispersion spectrophotometers. Fourier transform spectrophotometers: Time domain and frequency domain, Fourier transform, Michelson interferometer. Sources. Detectors. IR spectrum characteristics and interference. Cells for gas and liquid analysis. Solids analysis. Diffuse reflectance. Total attenuated reflectance. Microscopy.

4. Molecular spectroscopy - Raman

General characteristics. Raman effect. Polarizability. Comparison with IR spectroscopy. Raman signal strength. Depolarization ratio. Resonance-enhanced Raman Scattering. Surface-enhanced Raman Scattering. Sources. Dispersive and Fourier transform spectrometer. Raman microscopy.

5. Atomic spectroscopy

Instrumentation for atomic absorption, emission and fluorescence. Atomic absorption. Atomic absorption instrumentation. Atomic emission spectrometry: inductively coupled plasma sources.

6. Mass spectrometry

Fundamental. Ion sources: ICP, EI, CI, FD, FAB. SIMS, LD-MS, MALDI, ESI. Mass analyzers: magnetic sector, quadrupole, time of flight, ion trap, ICR-MS. Mathieu equation, secular frequency, ion trapping, isolation, resonant excitation, SIM, MS / MS experiments, hyphenate techniques.

7. Electroanalytical methods

Galvanic cell. Electrode potential. Nernst equation. Electrolytic cell. Junction potential, salt bridge. Double electric layer. Electroanalytical methods. Ohmic potential. Electrode polarization: concentration, reaction, adsorption, desorption, crystallization, charge transfer, mass transport. Reference electrodes: hydrogen standard, calomel, Ag / AgCl. Indicator electrodes: first, second and third species, redox, membrane. Glass electrode: glass, interphase potential, asymmetry potential, calibration, alkaline and acid error. Combined glass electrode. Potentiometer, load error, voltage trackers. Main electroanalytical techniques: potentiometry, voltammetry, amperometry.

8. Statistics of repeated measures

Absolute and relative error. Types of errors. Accuracy and precision. Descriptive statistics: Histograms, Position parameters, mean, mode, median, quartiles. Parameters of

dispersion: variance, standard deviation, standard error, relative standard deviation. Probability distributions. Binomial distribution. Poisson Distribution, Normal Distribution, Standardized Normal Distribution, Student Distribution, χ2 Distribution, Fisher-Snedecor Distribution. Statistical Inference. Estimation theory, sample mean distribution, sample variance distribution. Central limit theorem. Confidence interval for the mean and for the variance and for the difference between two means. Hypothesis test. Significant figures. Correlation between variables, covariance, correlation coefficient. Linear regression: least squares method, standard deviation of the regression, slope, intercept and values deduced from the line, goodness of fit, coefficient of determination. Matrix effect, recovery, method of standard additions. Sensitivity. Limit of detection and quantification.

9. Construction of a photometer for absorbance measurements:

Printed circuits. Symbols for electronic components. Ohm's law, Kirchhoff's law, voltage divider and current divider. Resistances and related conventions. Intrinsic and extrinsic semiconductors, p and n dopants. Diodes: forward and reverse polarization. Light emitting diode (LED). Photoresistors. Operational amplifiers: comparison devices, voltage trackers, inverting operational amplifiers.

Photometric determination of iron in aqueous solutions.

10. Potentiometric titrations

Determination of the phosphoric acid content in Coca-cola by potentiometric method.

## Textbook Information

-Class notes

-Skoog, Leary, “Chimica Analitica Strumentale”, Edises.

-Skoog, West, Holler, Crouch, “Fondamenti di Chimica Analitica”, Edises

-Rubinson, Rubinson, “Chimica analitica strumentale”, Zanichelli

The slides of the lessons and any educational material for further information are made available on Studium.

## Learning Assessment

### Learning Assessment Procedures

Class and laboratory experiments.

Should teaching be carried out in mixed mode or remotely, changes with respect to previous statements may be introduced, in line with the outlined syllabus.

According to safety requirements linked to the pandemic, learning assessments may also be carried out online.

### Examples of frequently asked questions and / or exercises

-Difference between energy and intensity of an electromagnetic radiation

-Choice of sources used for Raman Spectroscopy

-How can we derive the mathematical relationship for the calculation of a confidence interval of a parameter of a population