The course is part of the core educational activities of Bachelor's Degree in Sustainable Chemistry and Technologies (Curriculum SCIENCES AND TECHNOLOGIES OF BIO AND NANOMATERIALS). Aim of this second part of the course is to investigate the chemical-physical properties of the materials that determine their electrical behavior when interacting with electric or magnetic fields or with electromagnetic radiation. The course will analyze the chemical-physical reasons that explain, for example, why metals conduct electricity and heat better than plastic, why some materials have a specific color, such as ruby, while others, like glass, are more or less transparent. The course deals with the study of these properties starting from the classical physical models and then passing to the use of the principles of quantum mechanics introduced in the first part of the course. The course highlights how these materials are used in the construction of many devices that we use every day and that the development of sustainable technologies derives from our ability to control their properties with extreme precision.