A detailed outline of theChemistry vertical has been completed.
Introduction to Our Chemistry Course
Scientific concepts and laws are often taught by a method that can be described as “theory-first” or “top-down.” In chemistry, students are typically confronted with electron orbits before they learn about common metal ores. They are confronted with the periodic table and molecular formulas before they learn some simple facts that are used to distinguish mixtures from substances. Unfortunately, this method trains students to passively memorize abstract theory. The chemical elements, with their atomic weights and valences, electron shells and bonding characteristics, are given at the outset. Experiments are diminished to the role of merely illustrating aspects of the theory.
In fact, however, theory is the end result of a fascinating discovery process. Ancient chemistry started when people accidentally caused strange transformations in materials. This was how they learned to purify metals, which led to the bronze and iron ages. Modern chemistry started after scientists learned how to plan a series of experiments and quantify the results. The laws of the new chemistry were then combined with laws of motion and heat (discovered by physicists) to arrive at the atomic theory.
In our chemistry course, we start with the common metal ores. Historically, human life was revolutionized by knowledge of how to distil pure metals from odd-looking rocks. The metal ores come in two varieties: sulfides and oxides. It is best to start with the metal sulfides because sulfur is a solid that can be observed after chemical decomposition, whereas oxygen is an invisible gas that disappears into the air. Thus we introduce copper, iron, lead, mercury, and zinc by discussing their sulfide ores.
The atomic theory of matter is not assumed but proven in our course. This requires us to discuss in some depth the physics of gases and heat, because these topics play an essential role in deriving the correct atomic weights and valences. We arrive at the periodic table of atomic elements in the same way that Mendeleyev did, and students grasp the entire chain of inductive reasoning that led to this historic achievement. Throughout, our focus is on the inductive logic of the subject, and in every case we answer the question: How do we know this generalization is true? As a means to this end, we include many fascinating stories about the history of science. The student learns how to think like a scientist—and the theory is understood from evidence, not accepted on authority.
In the final sections of the course, we present the great 20th century discoveries regarding atomic structure, as well as some of the practical benefits that have emerged from this fundamental theory.
A century ago, a high school chemistry teacher (Robert Bradbury) wrote: “The systematic study of chemical changes by means of the balance is comparatively a new thing. During this short time it has proved to be the most important business to which men have ever turned their attention. It has revolutionized the conditions of life, and conferred benefits upon the human race which are quite beyond calculation.”
Our inductive approach leads students to grasp this profound truth.