SUMMARY Hopefully, the course on college chemistry you have just studied has provided a way for you who have been pursuing an interest in chemistry or who have possibly already been struggling with chemistry to understand this discipline in a much clearer way. As you have seen, chemistry is a wide-reaching subject, ranging from “physical chemistry” or the study of atoms, molecules, chemical reactions, and the properties of solids, liquids, and gases, to things like “organic chemistry” and “biochemistry” that deal with the topic of the chemistry specific to carbon-based molecules, which are the molecules of living things. As you have hopefully determined in studying this course, the majority of chemistry is about the physical properties of atoms and molecules in singular form as well as the physical properties of molecules in different states, including the molecular properties of gases, solids, and liquids. Most atoms and molecules are not inert and interact with one another in specific chemical and physical ways. This has been the major focus in this course as we learned about how different substances exist in natural and experimental situations. Chapter one in the course introduced chemistry in its most basic form by covering atoms and their nature. Everything in the universe is made from different types of atoms. As it turns out, atoms have specific sub-particles that make up the basic structure of the atom. There are also numerous different atoms in nature, as we talked about when introducing the periodic table, which outlined the relationships between different types of atoms. Finally, there was a discussion on the concept of the “mole” as it exists in understanding quantities of atoms and molecules. The focus of chapter two was the structure of atoms. As you have seen, there are specific rules that define how subatomic structures are organized. This chapter looked at the arrangement of electrons, and both the Pauli principle and Aufbau Principle, which define electron relationships inside the atom. Electrons have a natural affinity for the
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