Benzene from Coal and Lye?
[caption id="attachment_17736" align="alignright" width="480"] Coal and Lye[/caption] As a youth, I read whatever chemistry books I could get hold of. One made reference to an obscure synthesis of the liquid aromatic compound benzene from coal and lye, by means of heat. This reaction would seem to be an improbable one. Can a stoichiometric equation be written for such a synthesis? The answer is, Yes. This in itself does not guarantee the reaction can actually take place. 6 NaOH + 9 C → 3 Na2O + C6H6 + 3 CO I learned of this synthesis from an old book, possibly published in the 1800s. Coal and Lye - What Conditions? Such a reaction strongly suggests isolation. The reaction required considerable heat. Also, air was to be excluded, since carbon would react…
Graphene Properties, Applications, and Production
[caption id="attachment_16970" align="alignright" width="406"] Graphene Lattice - By AlexanderAlUS - Own work, CC BY-SA 3.0[/caption] Carbon varieties include diamonds, graphite1, soot, Buckminsterfullerene, and tiny nanotubes. Despite these amazing forms, there is still another form of carbon, perhaps the most amazing of all. Graphene. Discovery Graphene is a super material. For its successful isolation, André Geim and Konstantin Novoselov, were awarded the 2010 Nobel prize. Each sheet is one atom thick. It resembles a hurricane fence. First Production The first effort at isolation involved thinning a pad of graphite. Adhesive tape was attached to the sides of the pad it was pulled apart. In time, a single layer was left. There are two easy ways to visualize this. First, imagine a flaky biscuit with many layers. You peel the layers off,…
Cubane: The Chemist’s Toy?
Cubane is an organic hydrocarbon. It consists of carbon and hydrogen and is cubic in shape. It is a very curious substance, indeed. With no practical purpose in view, it was first prepared in 1964. There is an endless number of theoretical molecular possibilities in the world of organic chemistry. Some chemicals are simple. Others are complex. Some are of practical use to mankind. Some are mere toys of the intellect. Yes, adults must have their toys! Cubism "We do the difficult immediately. The impossible takes a little time." Chemists enjoy challenges. One challenge was to synthesize cubane (C8H8). It is a cut with a carbon atom at each corner. Attached to each of them is one hydrogen atom (see the image). Now carbon "prefers" to form angles of 109.5…
Why Sulfuric Acid Turns Sugar Black
Sugar is white. Sulfuric acid is colorless. So how is it sulfuric acid turns sugar black? Table sugar is actually two sugars in one—a disaccharide. It is commonly known as sucrose. Sucrose is a combination of fructose, a sugar found in fruits, and glucose, known also as blood-sugar, grape-sugar, and corn-sugar. Its chemical formula is C₁₂H₂₂O₁₁. The way these atoms are attached to each other by chemical bonds determines its structural formula. In the Left Corner… Most sugar from a grocery store is granular and pure white. If the grains are large enough—existing as large crystals—it is immediately apparent that sugar isn't even white; it is totally colorless and transparent. Sold at candy stores, we call it rock candy. [sc name="MidArticleAdsense"] In the Right Corner… Concentrated sulfuric acid is thick…
What are Allotropes?
[caption id="attachment_6012" align="alignright" width="440"] Cyclooctasulfur (S8)[/caption] What are allotropes? An allotrope is one of a variety of forms in which an element can exist. This does not refer to the state of an element, whether solid, liquid, gas, or plasma. It refers to the tendency of an element to exist in different structural forms. Allotropes of Carbon Thus carbon can be found in a variety of forms, including graphite, charcoal, diamond, fullerenes, and nanotubes. Of Sulfur Sulfur allotropes take an assortment of forms. These include rings that range from six to twenty atoms. Especially well known are the monoclinic and rhombic crystalline forms. Of Phosphorous Phosphorus allotropes exist in a variety of colors. Ordinary phosphorous is called white phosphorous (P₄). It is unstable and dangerous. But there are also red,…