Tetrahydrofuran or Diethyl Ether – Which to Use?

Tetrahydrofuran (C4H8O) is a heterocyclic hydrocarbon. One of the carbon atoms of a cyclopentane ring (along with its two hydrogen atoms) is replaced by an atom of oxygen. THF is an ether. It's frequently used for its solvent properties. In certain organometallic reactions, tetrahydrofuran replaces all or part of the standard solvent diethyl ether, (C2H5-O-C2H5), written in chemists' shorthand Et-O-Et. Tetrahydrofuran Vs. Diethyl Ether Although THF is essentially diethyl ether gone cyclic, its physical properties differ somewhat. A prime example of that relates to hydrogen bonding. Although both molecules possess an electron-rich oxygen atom, in THF, the oxygen is openly exposed. The ring can twist, but that's about it. The hydrocarbon portions of ethyl ether¹ have much greater freedom of motion. They can sweep around, making hydrogen bonding easier to…
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Why Metals Conduct Electricity

Electrical, Physics
[caption id="attachment_19272" align="alignright" width="480"] High Voltage Lines.[/caption] Elements are divided into metals, metalloids, and non-metals. Copper is a metal. Sulfur is a non-metal. Antimony is a metalloid. Why do metals conduct electricity? What makes them special? It involves electron mobility—their ability to move about. Individual Atoms and Diatomic Molecules Atoms have a positive nucleus encased by negative orbiting electrons. Atoms of a single substance either stand alone or bind together in small groups only. Helium (He) is monatomic. Hydrogen (H₂) is diatomic. Ionic and Covalent Crystalline Solids Some solids may form crystals. The atoms are packed close together. There are three crystal types. Ionic, covalent, metallic. Ionic crystals conduct some electricity. They are not as conductive as metals because their bonds are local. Their crystals are rigid. They fracture. They…
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