This book, together with the three other volumes, offers a clear and comprehensive approach to theoretical physics for the entire Bachelor's program. Highlights: Theoretical derivations are linked with characteristic examples, their solutions, typical applications, and are clearly illustrated in figures. The required mathematics is derived within a physical context and transparently explained. Contents: Statistical Ensembles - Identical Particles - Concept of the Statistical Ensemble - Statistical Definition of Entropy - Statistical Ensembles in Equilibrium - Independent Identical Particles - Statistical Mechanics and Thermodynamics - Small Deviations from Equilibrium - The Ideal Fermi Gas - The Ideal Bose Gas - Real Gases - Magnetic and Electric Properties of Matter - Kinetic Theories Target Audience: This book is particularly suitable for Bachelor’s students in their final year. Prerequisites: Mathematical prerequisites include knowledge in calculus, linear algebra, and complex analysis. The Author: Wolfgang Cassing is a retired Professor of Theoretical Physics at the Justus-Liebig-University Gießen. His expertise lies in the phase-space dynamics of classical and quantum many-body systems, which he incorporated into his textbook "Transport Theories for Strongly-Interacting Systems". His current textbook series Theoretical Physics Compact also includes Classical Mechanics, Electrodynamics, and Quantum Mechanics.