04422 - General Chemistry

Learning outcomes

The course aims to provide basic notions of chemistry, such as the composition, structure, and reactivity of molecules, stoichiometry, and the equilibrium of chemical reactions for homogeneous and heterogeneous systems. The student will also gain the ability to apply this knowledge to solve numerical and practical problems.

Course contents

Prerequisites

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

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

Knowledge of chemistry is not a prerequisite for the course.

MODULE 1

Learning Unit 1A - STRUCTURE

1A.1 - Introduction and fundamental concepts. Homogeneous and heterogeneous systems, substances and mixtures, elements and compounds.
Atoms and subatomic particles, atomic symbols, atomic and mass number, isotopes, ions.
Atomic mass and atomic weight, minimum formula and molecular formula, formula weight and molecular weight, mole.

1A.2 - The atom. Wave-particle dualism, and quantum model of the hydrogen atom and of polyelectronic atoms. Orbital shells and sub-shells, quantum numbers, electronic configurations.
The periodic table and periodic properties of chemical elements.

1A.3 - The chemical bond. The covalent bond; Lewis formulas, bond length and energy; electronegativity and bond polarization. Molecular geometry. Valence bond theory, hybrid atomic orbitals, multiple bonds.
The ionic bond; characteristic properties of ionic compounds.
The metallic bond; alloys.
Intermolecular forces: London forces, dipole-dipole forces, hydrogen bonds.

1A.4 - Gases, liquids, solids. Properties of gases: ideal gas law, partial pressures, real gases.
Liquids: vapor pressure, melting and boiling points. The solid state: outline of physical properties of solids.
Allotropic forms of the major elements. State diagrams, phase transitions.
Introduction of gaseous and liquid solutions; expressions of concentration.

Learning Unit 1B - TRANSFORMATIONS

1B.1 - Chemical thermodynamics. Heat and energy.
Chemical transformations: basic concepts.
First principle of thermodynamics, state functions, reaction enthalpy; thermodynamic standard state.
Entropy and its significance. Second and third principles of thermodynamics.
Spontaneous reactions, Gibbs free energy.

1B.2 - Chemical equilibrium. Gas-phase equilibria; complete and incomplete reactions. Heterogeneous equilibria.
Equilibrium constant and reaction quotient. Le Châtelier principle; effect of state variables on equilibrium.
Thermodynamic significance of equilibrium.

1B.3 - Electrochemistry. Galvanic cells, electrodes, standard potentials.
Nernst equation; concentration cells and glass electrode. Electrolysis. Fuel cells. Corrosion of metals.

1B.4 - Chemical kinetics. Reaction rate, kinetic law and rate constant; integrated first- and second-order kinetic equations.
Reaction mechanism, order and molecularity, elementary processes, rate-determining step.
Activation energy, Arrhenius equation; elements of collision theory; homogeneous, heterogeneous and enzymatic catalysis.

MODULE 2

Learning Unit 2A - CHEMICAL REACTIONS AND EQUILIBRIA IN SOLUTION.

2A.1 - Moles and chemical formula. Moles and molar mass. Minimum formula and molecular formula, percentage composition, analysis by combustion, stoichiometry of mixtures.

2A.2 - Chemical reactions and equations. Chemical equations and their balancing; limiting reagent. Yield.
Oxidation number; nomenclature; major categories of compounds. Classes of chemical reactions: acid-base and oxidation-reduction; balancing of redox reactions.

2A.3 - Solutions. Concentration and its expressions. Preparation and dilution of a solution. Stoichiometry of reactions in solution. Prediction of solubility of solutes in solvents.

2A.4 - Acid-base equilibria in water. Self-ionization of water. Definition of acids and bases, the pH scale; strength of acids and bases. Calculation of pH of strong and weak acids and bases. Titration curves, buffer solutions, acid-base indicators.

2A.5 - Solubility equilibria. Heterogeneous equilibrium: poorly soluble salts, solubility and solubility product. Common ion effect. Formation of a precipitate. Fractional precipitation. Solubility and pH.

Numerical exercises will be carried out during Module 2 “General Chemistry Laboratory” mainly on the topics covered in Learning Unit 2A. The lectures and numerical exercises will be supplemented by hands-on laboratory experiences; all the necessary knowledge for full understanding of the relevant experiences will be provided during the classroom lectures.

Readings/Bibliography

It is advised to consult any of the many chemistry texts (basic chemistry, elements/fundamentals of chemistry) at the University undergraduate level (no high school texts). Some suggestions are:

• A. Credi, A. del Zotto, A. Gasparotto, F. Marchetti, D. Zuccaccia, Viaggio nella Chimica, EdiSES

• I. Bertini, C. Luchinat, F. Mani, Chimica, CEA

• R. Chang, Fondamenti di chimica generale, McGraw Hill

• A. M. Manotti Lanfredi, A. Tiripicchio, Fondamenti di chimica, CEA

• P. M. S. Silberberg, Chimica, McGraw Hill

• F. Nobile, P. Mastrorilli, La chimica di base, CEA

• L. Palmisano e altri, Elementi di chimica, EdisesFor useful and enjoyable further reading:

V. Balzani, M. Venturi, Chimica! Leggere e scrivere il libro della natura, Scienza Express, Trieste, 2012

The course materials, including the lecture slides, are made available by the professors before the start of the course through the University repository, https://virtuale.unibo.it/. The latter is accessed using the credentials of the @studio.unibo.it account. To facilitate preparation for the final exam, numerous exercises and problems (with and without solution) of the same type as the written test are provided as supporting materials.

Teaching methods

Classroom lectures supplemented by numerical exercises on the topics covered. The course is supported by General Chemistry Laboratory activities and experiences aimed at testing and verifying lecture content and developing skills in basic operations in the chemical laboratory.

Laboratory activities require mandatory attendance of hands-on experiences. Each student is required to produce his/her own “laboratory notebook” in which the experiences performed are described and discussed, which must be handed in before the oral test. Attendance will be ascertained by signing a form at the end of each laboratory experience. Any exceptions will be subject to evaluation by the professor in charge of the practical laboratory activities.

In order to facilitate the student's acquisition of a method of study that is appropriate to the characteristics of a university course, and to facilitate the overcoming of any difficulties, the opportunity is offered to carry out exercises in the classroom in the presence of a teaching tutor selected by the University. The tutor's task is to accompany students in solving problems and exercises, and to clarify any doubts that may arise during individual study. In this regard, please note that the professor is always available to provide clarification in the margin of lectures or through meetings in the office.

Attending lectures is strongly recommended. However, studying only on slides and lecture notes is usually not sufficient; it is important to complete the preparation with the help of a textbook. It is also advised to take full advantage of the support services offered by the teaching tutor.

Assessment methods

The assessment of the learning outcomes is performed by means of a comprehensive final test consisting of a written and an oral part. The written test includes answering theory questions and solving numerical problems and exercises, and is considered passed with a score of 18/30 or higher. The student has a time limit of two hours and cannot consult notes or books, while he/she can use the periodic table and the list of fundamental constants, which will be provided at the exam. A scientific calculator is required. Registration through AlmaEsami is mandatory in order to take the exam in the scheduled appointments, in strict compliance with the indicated deadlines.

The oral test can be taken only after passing the written one. The oral exam is aimed at verifying the acquisition of the knowledge provided by the course objectives, and will be considered passed if a correct answer is given to the majority of the formulated questions. The average duration of the oral test is 15-20 minutes; passing it leads to the final grade, which is also determined by taking into account the score obtained in the written test. Both the content of the theory and laboratory modules contribute to the final grade. No in-progress (partial) tests are foreseen.

Students with learning disabilities (LD) or temporary or permanent disabilities are advised to contact the University office in advance, which can advise them on any exam adaptations. These adaptations must be submitted to the instructor for approval at least 15 days before the exam date, who will evaluate their suitability, also taking into account the course's learning objectives.

Teaching tools

Powerpoint slides and whiteboard are both employed at lectures.

A teaching tutor will be appointed to support learning.

Office hours

See the website of Alberto Credi

See the website of Cristiana Cesari