Rare Earth Metals – 17 Special Elements

Chemistry, Technology
[caption id="attachment_23646" align="alignright" width="480"] Rare Earths. Photo ARS-USDA by Peggy Grubb.[/caption] Most of us are familiar with elements – the building blocks of matter. Most of us know about elements such as oxygen, nitrogen, carbon, sulfur, sodium, and helium. Yet, there are other elements few have even heard of, despite their immense technological and medical importance. Are you familiar with the rare earth metals? Allow me to introduce them: what are they good for, and where do they come from? Rare Earth Metals Among the less commonly known elements are the rare earth metals. These elements have many important uses, such as: Rare earth metals are used in heat-resistant, powerful, permanent magnets. They are employed in superconductors for cryogenics applications. They are used in pyrophoric alloys for initiating combustion. And…
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Hydrogen Metal?

Chemistry
We're familiar with hydrogen as a gas, but hydrogen metal? Could it be that's what hydrogen is? [Artist's conception at right.] There are more than 100 substances listed in the Periodic Table of the Elements. This table is called "periodic" because, although each column is completely different, the properties of one row are very similar to the properties of the next. If you start on the left with an alkali metal, and you go through a row, you go to the next row and another alkali metal. An Anomaly Most of the alkali metals, such as lithium, sodium, and potassium, are very similar. They are soft, reactive, silvery solids. They have one outer electron and conduct electricity. They are easily cut with a knife. But, there is an exception –…
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Inert Gas Compounds?

Chemistry
[caption id="attachment_16914" align="alignright" width="440"] Xenon Tetrafluoride[/caption] There are millions of compounds. Some of them are even inert gas compounds. We were taught in high school that there are special, inert gases in the Periodic Table. These include radon and krypton, and are found in the column furthest to the right of the table. But that was then. Now we will learn that not all of those gases are all that inert. In addition to being called inert, the far right column gases are sometimes called rare or noble gases. These gases have a completed outer shell of electrons. So it would seem they should have no tendency to gain or lose electrons. But just how true is that? Can inert gases form compounds? Platinum Hexafluoride Platinum hexafluoride is formed by…
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Calculate Atom Weight Two Ways

Physics
[caption id="attachment_8437" align="alignright" width="400"] Radon atom statistics.[/caption] Ever wonder how much an atom weighs? One atom. Different varieties of atoms weigh different amounts—helium weighs one thing, lead another. But how can the weight of any sort of atom be determined to within reasonable accuracy? We present two simple methods to calculate atom weight. Two Ways One can calculate atom weight from knowing the weights of the constituent electrons, protons, and neutrons. If you know the weight of each of those and the number of each in an atom, you can readily calculate its weight. Yet, there is an easier and a better way. Let’s pick an element out of the hat. Let’s take gold (If we can’t afford it, at least we can talk about it.). To calculate atom weight…
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