38837 - General Chemistry

Learning outcomes

At the end of the course, the student knows the theoretical foundations necessary for understanding the structure of matter, in its atomic and molecular constituents. The scientific treatment of the phenomena underlying the transformation of food is acquired with models suitable for the rigorous description of the stability and kinetic aspects.

Course contents

Prerequisites

Knowledge of the main elementary arithmetic and mathematical functions: fractions, powers, roots, exponentials and logarithms. Scientific notation. Solution of first- and second-degree algebraic equations.

Knowledge of the main physical quantities and the relationships between them, the principal units of measurement of the International System of Units (SI), and commonly used non-SI units. Scalar and vector quantities.

Previous knowledge of chemistry is not a prerequisite for the course.

The Chemistry course is divided into four teaching units:

• Structure of Matter

• Transformations of Matter

• Numerical Problem-Solving Sessions

• Chemistry Teaching Laboratory

COURSE CONTENTS (6 ECTS CREDITS)

Teaching Unit 1: Structure of Matter (16 hours)

1.1 Chemical classification of matter

Elements and compounds, pure substances and mixtures. Atomic symbols, atomic number and mass number, isotopes, ions.

1.2 Atomic weight, chemical formulae and the mole

Atomic mass, atomic weight, formula weight and molecular weight; the mole.

1.3 Atomic structure

The hydrogen atom and multi-electron atoms. Orbitals, quantum numbers and electron configurations. Periodic properties.

1.4 Chemical bonding

Covalent bonding: Lewis structures, electronegativity, molecular geometry and polarity; valence bond theory, hybrid orbitals and multiple bonds. Molecular orbital theory: introductory concepts. Ionic bonding and ionic lattices. Metallic bonding: introductory concepts. Intermolecular forces and hydrogen bonding.

1.5 Gases, liquids and solids

Properties of ideal gases and partial pressures; introductory concepts of molecular kinetic theory. Liquids: vapour pressure, melting point and boiling point. Structure and physical properties of solids: introductory concepts. Allotropic forms of the main elements.

Teaching Unit 2: Transformations of Matter (20 hours)

2.1 Chemical equations and main classes of compounds

Balancing chemical equations, stoichiometric calculations and limiting reagents. Oxidation numbers; oxidation-reduction reactions: principles and balancing. Introduction to the main classes of inorganic compounds: oxides, hydrides, acids, bases and salts.

2.2 Chemical thermodynamics

Heat, work and energy; the first law of thermodynamics, state functions, enthalpy of reaction and formation, standard states and Hess’s law. Spontaneous processes: entropy. The second and third laws of thermodynamics. Gibbs free energy.

2.3 Solutions

Molarity and other ways of expressing concentration. Dilutions. Colligative properties and osmotic pressure. Solubility.

2.4 Chemical equilibrium

Gas-phase equilibria. Complete and incomplete reactions; equilibrium constant, reaction quotient, effect of temperature, Le Châtelier’s principle; meaning and use of the equilibrium constant.

2.5 Equilibria in aqueous solution: acids and bases

Properties of acids and bases according to the Brønsted-Lowry model, conjugate acid-base pairs and amphoteric compounds. Self-ionisation of water. pH: definition and calculation for strong and weak acids and bases; degree of dissociation. Salt hydrolysis and its effect on pH. Buffer solutions and acid-base titrations.

2.6 Solubility equilibria

Behaviour of sparingly soluble salts. Solubility and solubility product. Common-ion effect.

2.7 Electrochemistry

Electrochemical cells, electrodes and standard potentials; introductory concepts of the Nernst equation. Glass electrode for pH measurement. Introductory concepts of electrolysis.

2.8 Chemical kinetics

Reaction rate, rate law and reaction order. Integrated rate equations for first- and second-order reactions. Reaction mechanisms and rate-determining steps. Activation energy, the Arrhenius equation and introductory concepts of collision theory.

Teaching Unit 3: Numerical Problem-Solving Sessions (16 hours)

Problems involving acid-base and redox reactions.

Problems in chemical thermodynamics.

Problems in chemical kinetics.

In-class simulation of the written examination, covering the six possible types of exercises: IUPAC nomenclature, structural formulae, pH, reduction potential, thermodynamics and chemical kinetics.

Teaching Unit 4: General Chemistry Laboratory (8 hours)

Laboratory safety.

Laboratory activity on the separation of heterogeneous mixtures.

Laboratory activity on acid-base titration.

Laboratory activity on redox titrations.

Readings/Bibliography

Title: Lezioni di Chimica Generale
Authors: Marco Sola
Publisher:EdiSES
Pages:758
ISBN: 978 88 3623 204 8


Title: Chimica
Authors: Bertini Ivano, Luchinat Claudio, Mani Fabrizio
Publisher: CEA
Pages: 512
ISBN: 8840812857


Title: Viaggio nella Chimica
Authors: Alberto Credi et al.
Publisher: EdiSES
Pages: 481
ISBN:978 88 3623 111 9

Teaching methods

The course comprises 6 ECTS credits, corresponding to 60 hours. For each ECTS credit, 60% of the hours are devoted to lectures and 40% to classroom or laboratory practical activities.

The practical activities are carried out in the Chemistry Laboratory at the Cesena Campus (Villa Almerici), which is equipped with 30 workstations, each provided with glassware and basic instrumentation, including pH meters, magnetic stirrers and hot plates.

The practical activities have two main objectives:

• to enable students to become familiar with laboratory equipment and chemical laboratory safety regulations;

• to develop students’ ability to relate the results of empirical experiments to the knowledge acquired during lectures.

Given the nature of the activities and the teaching methods adopted, participation in this training program requires prior participation in Modules 1 and 2 via e-learning and participation in Module 3, which specifically focuses on health and safety in the workplace. Information on the dates and methods of participation in Module 3 can be found in the dedicated section of the program website.

Assessment methods

The final examination is designed to assess whether the following learning objectives have been achieved:

• the ability to describe food matter through simplified models capable of accounting for its observed properties;

• the ability to describe the chemical composition of foods using appropriate terminology and scientific rigour;

• the ability to describe the phenomena involved in the transformation of substances.

The examination consists of a two-hour written test followed, upon successful completion and after a few days, by an oral examination.

The written test comprises six exercises covering IUPAC nomenclature, molecular structures, chemical equations, and numerical problems involving the application of concepts learned during the course, with particular reference to solutions and their properties, pH, solubility, electrochemistry, thermodynamics, and kinetics.

Each exercise contributes a maximum of one point to the total score, which may also be awarded fractionally. The total score for the written test may therefore range from 0 to 6 points.

The first two exercises, concerning nomenclature and structural formulae, respectively, are compulsory. Fractional scores may also be awarded for these exercises. In the nomenclature exercise, for example, the score will depend on the number of correct answers out of the total number of questions.

For the exercise on molecular structures, students are required to provide the most representative structural formula among the possible resonance contributors, together with the electron-domain geometry, molecular geometry, hybridisation of the central atom, and bond order between the peripheral atoms and the central atom. Any incorrect or missing information will result in a proportional reduction in the score awarded for that exercise.

The written test is considered satisfactory if a score of at least 2 points is achieved. This is a necessary condition for admission to the oral examination.

The oral examination will begin with the topics addressed in the written test and will include appropriate theoretical discussion of all topics covered in the course syllabus.

The main purpose of the written test is to verify that the conditions required for admission to the oral examination have been met. For this reason, only two alternative outcomes will be published on AlmaEsami: “admitted” or “not admitted”. A numerical grade will be assigned only upon completion of the examination as a whole.

It should be noted that the Chemistry examination is a single examination and that the written and oral tests represent two stages of a single assessment process, which should normally be completed within the same examination session.

However, where appropriate, for example in the event that the oral examination is not passed, students may be allowed to retake it in a subsequent examination session or, where justified by specific circumstances, within one year of passing the written test. This possibility does not alter the principle that the examination constitutes a single assessment, while recognising that a reasonable degree of flexibility may be beneficial to students without compromising the rigour of the final evaluation.

In practice, the possibility of postponing the oral examination is granted when the written test result is clearly above the minimum passing threshold, namely above 5 points, on the principle that such a result provides evidence of preparation that is sufficiently broad and likely to remain stable over time. By contrast, when preparation is only just sufficient, a prolonged postponement could risk turning the examination into a remedial assessment of individual weaknesses rather than a comprehensive evaluation of the knowledge acquired.

Examinations will be held in person.

Students with learning disorders and\or temporary or permanent disabilities: please, contact the office responsible as soon as possible so that they can propose acceptable adjustments. The request for adaptation must be submitted in advance (15 days before the exam date) to the lecturer, who will assess the appropriateness of the adjustments, taking into account the teaching objectives.

Teaching tools

The teaching materials presented during lectures will be made available to students in electronic format on the Virtuale platform.

Audio recordings of lectures may be permitted, provided that they are made available to all students by sharing the MP3 files in restricted-access areas of the lecturer’s website.

Office hours

See the website of Francesco Capozzi