Chemistry is a branch of science that focuses on the study of matter, its properties, composition, structure, and the changes it undergoes during chemical reactions. While quantum mechanics, described by equations like the Schrödinger equation or Dirac equation, provides a fundamental framework for understanding the behavior of atoms and molecules, it is not sufficient to explain and predict all aspects of chemical phenomena. Here are a few reasons why chemistry is necessary:
Bridging macroscopic and microscopic worlds: Chemistry helps bridge the gap between the macroscopic world we observe and the microscopic behavior of individual atoms and molecules. It provides a framework for understanding how the properties and behaviors of atoms and molecules give rise to the properties of matter on a larger scale.
Complexity of chemical systems: Chemical systems can be incredibly complex, involving a large number of interacting particles. While the fundamental equations of quantum mechanics can describe the behavior of individual particles, solving these equations for large systems becomes computationally intractable. Chemistry provides simplified models and approximations that allow us to understand and predict the behavior of complex chemical systems.
Chemical bonding and reactivity: Chemistry focuses on understanding how atoms combine to form molecules through chemical bonding. Chemical reactions involve the breaking and forming of these bonds, and chemistry provides the necessary concepts and tools to analyze and predict the outcomes of these reactions. Quantum mechanics alone cannot provide a complete picture of chemical bonding and reactivity.
Descriptive power: Chemistry encompasses a vast array of experimental observations, classifications, and principles that help us understand and categorize the properties and behavior of different substances. It provides a descriptive language and a systematic framework for organizing and explaining the immense diversity of chemical compounds and their behaviors.
Applied and practical applications: Chemistry plays a crucial role in various applied fields such as medicine, materials science, energy production, environmental science, and more. Understanding chemical principles is essential for developing new drugs, designing materials with specific properties, developing sustainable energy sources, and addressing environmental challenges.
In summary, while quantum mechanics provides a fundamental understanding of the behavior of matter at the atomic and subatomic level, chemistry complements it by providing a broader framework to understand and predict the properties, behavior, and interactions of complex chemical systems. Chemistry helps us bridge the gap between microscopic and macroscopic worlds, understand chemical bonding and reactivity, and apply our knowledge to practical applications.