I like chemistry more than I remember from school. My high school chemistry teacher spent the first six weeks of school instructing us in the phonetic-mnemonic memory system. He could use the system to memorize the order of a deck of cards. The purpose of the instruction was to prepare us for memorizing the periodic table.
Looking back, that was a waste of time. The system is useful; maybe he could have used one class to introduce it and encourage all of us to practice on our own time. But memorizing the periodic table seems useless to me. Even in that 1983-pre-internet age, printouts of the periodic table were not hard to come by. Maybe professional chemists, over years of constant use, commit some or all of the table to memory. Maybe. A failure to memorize that table would not close the door on a chemistry profession for any us who would have chosen to go in that direction.
I also took the standard Chemistry course that all engineering students were required to take. My recollection: difficult.
I enjoyed reading this book because chemistry is neat. There are 103 naturally occurring elements, each with their own story. (There are an additional 14 or 15 human-created elements, depending on your standard-of-proof.) The titular example is as follows. Most metals are solid at room temperature, the only exceptions being mercury and bromine. Most other metals become liquids only high temperatures; for example, the melting point of iron is 2800 degrees Fahrenheit. A notable exception is gallium, with a melting point of 85 degrees Fahrenheit. Gallium is white/silver in color and not terribly expensive at about $1 per gram. If one were to fashion a lump of gallium in the shape of a spoon and put such a utensil in an empty tea cup, no one would notice. However, upon pouring the tea into the cup, the spoon would melt and disappear into the cup.
The discovery of the periodic table is one of the triumphs of modern science, organizing seemingly random materials into order. With the table we can predict, and explain, that carbon, silicon, germanium, tin and lead will behave chemically in similar ways. This is so because chemistry is the study of how one atom's electrons interact with another atom's electrons. Electrons "circle" the nucleus of an atom, which consists of protons and neutrons. The electrons circle in different orbits, each representing different energy levels, and the electrons in the highest orbit are the ones free enough to join up with the highest orbiting electrons of another atom. The elements carbon, silicon, germanium, tin and lead all have four electrons circling in their highest orbits. The structure of the table to the modern scientist is intuitive, but to the scientists of the 19th and early 20th centuries the structure had yet to be agreed upon. The work of Russian Nobel prize-winner Dmitri Mendeleev and others provided theoretical explanations for the work of experimental chemists. Further, gaps in the table showed experimental chemists where to look for new elements (the prize: for a while, the International Union of Pure and Applied Chemistry named new elements after the discoverer).
Most of us have read on some packages of salt: "this salt does [not] provide iodide, a necessary nutrient". In addition to preventing many types of birth defects, iodine is necessary for proper thyroid function. (Iodide is an ion of the element iodine; it is what you get when you mix iodine with some other chemical, such as potassium.) Improper thyroid function can lead to (among other things) goiter and mental retardation. Starting with Switzerland in 1922, many countries required the addition to iodide to table salt as a cheap and effective way of insuring a sufficient intake. The British, while in control if India, in their infinite wisdom, taxed the production of salt. This tax was one of the policies Gandhi protested against, so that after the years of independence, as Western scientists pushed India to iodized its salt, it resisted the colonial intrusion. To this day, iodine deficiency is a public health issue in India.
Marie Curie was one of the few people, and the only woman, to receive two Nobel prizes. She shared the first, in physics, with her husband; they discovered that uranium's physics (radioactivity) was different than its chemistry (how its electrons interact with the electrons of other elements). Thus, to study the radioactive properties of uranium, it was not necessary to separate it from whatever it was found in, such as pitchblende. Scientists need only study the radioactivity of ninety-some elements, not millions of chemical combinations. She earned her second prize in chemistry for her discovery of radium and polonium. You have probably heard her name before, even though you can name but a few other Nobel prize winners. This is probably due to her travels throughout the world, including the United States, where she introduced crowds to her glowing radium samples. She enjoyed barely-secret trysts with many men, including colleagues. She died in 1934 at age 67 from radiation poisoning, one year before her daughter, Irène, won her own Nobel prize in chemistry. Irène herself died from radiation poisoning at age 59.
Despite her fame and her accomplishments, Madam Curie seems to have little interest among biographers. I just now searched the Denver Public Library for additional titles. All of the first ten listings, and seventeen of the first twenty listings, came from the juvenile/youth section. Only three of the first twenty listings were books targeted to an adult audience.
Lithium, element 3, is a salt. It appears directly above Na, element 11 and the symbol for sodium, a more well-known salt. Doctors use it as a treatment for psychiatric illnesses, including manic-depressive (bipolar) disease. Robert Lowell, a Pulitzer prize-winning poet of the 1960s and 70s suffered from bipolar disease. He won his prize in 1974, seven years after starting his lithium use, though many critics prefer his work from the 1960s. The depressive phase of bipolar disorder arises when the brain becomes depleted after a manic phase. The manic phase arises because proteins in the brain that normally rise and fall with sunlight, do not fall. Sufferers have proteins that remain embedded in the brain; no signal for fatigue is detected, and the brain is happy to continue for days ... until depletion. Lithium helps the brain shed the proteins in the evening, when they should normally fall off.
I should note that, while Kean seems comfortable with the foregoing description of lithium's effects on bipolar users, others are not as sure. In fairness, Kean describes lithium's effects as "complicated."
I was in high school when I first read books about quantum mechanics and particle physics and about Heisenberg's uncertainty principle. I remember part of the explanation including the phrase "Observer-created reality". These books would describe the Schroedinger Cat thought experiment, where a cat was placed in a box along with a toxic-dose poisonous substance encased in a glass. A material with a half-life of a minute is placed in the box also; if this material decays it will trigger a geiger counter which is rigged to shatter the glass. Schroedinger asserted that after the half-life the cat was both dead and alive; the act of opening the box causes one or the other to occur. In my mind, this is a metaphysical, rather than a physics, assertion. The experiment parallels the particle-wave duality of light and applies to subatomic particles in ways not observable with human-sized objects. The Heisenberg uncertainty principle states that one's certainty regarding the position of an object is inversely related to one's uncertainty regarding that object's velocity.
Think of a car. We can see it as it crosses point A, and as it crosses point B. With a stopwatch and a ruler we can calculate its speed to whatever precision our watch and ruler afford. "See" means that photons of light bounce off the car and into our eyes. Photons have no appreciable mass in comparison to the weight of the car. A photon striking a subatomic particle however, is more like one billiard ball striking another. Perhaps they are not exactly sized, as in coin-operated billiards, but close enough such that the strike will substantially interfere with our ability to measure position or velocity or both.
Kean explained, to my astonishment, that the foregoing is somewhat inaccurate. The Heisenberg uncertainly principle is actually formula:
4 * Π * Δx * Δv >= Planck's constant
Delta-X is our uncertainty in position; delta-V our uncertainty regarding velocity. Planck's constant is very small, but not zero. The Bose-Einstein condensate, so-called because Einstein's work predicted it and Bose said so, is a form of matter that arises when one cools matter substantially. By substantially, we mean 1 billionth of a degree Kelvin. At such low temperature, atoms move hardly at all, and when the uncertainty regarding velocity is so small, the atoms become more confident about where they are positioned. In a University of Colorado experiment, scientists Eric Cornell and Carl Wieman reduced a few thousand rubidium atoms to this tiny temperature and observed them behave as a single, large "ghostly" atom. Their efforts netted them a portion of the 2001 physics Nobel prize.
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