How to Grow Ammonium Phosphate Crystals

How to Grow Ammonium Phosphate Crystals Monoammonium phosphate is one of the chemicals included in commercial crystal growing kits because it is safe and practically foolproof for producing a mass of crystals quickly. The pure chemical yields clear crystals, but you can add food coloring to get any color you desire. The crystal shape is perfect for green emerald crystals. Difficulty: Easy Time Required: 1 day What You Need Monoammonium phosphateHot waterClear container Growing Monoammonium Phosphate Crystals Stir six tablespoons of monoammonium phosphate into 1/2 cup of very hot water in a clear container. I use water heated from an electric drip coffee maker and a drinking glass (which I wash before using it again for beverages).Add food coloring, if desired.Stir until the powder is completely dissolved. Set the container in a location where it wont be disturbed.Within a day, youll have a bed of long, thin crystals blanketing the bottom of the glass, or perhaps a few large, single crystals. Which type of crystals you get depend on the rate at which the solution cools. For large, single crystals, try to cool the solution slowly from very hot down to room temperature.If you get a mass of crystals and wanted one big crystal, you can take a small single crystal and place it in the growing solution (either new solution or the old solution that has been cleared of crystals) and use this seed crystal to grow a large, single crystal. Tips If your powder doesnt completely dissolve, it means your water probably should have been hotter. Its not the end of the world to have undissolved material with these crystals, but if it concerns you, heat the solution in a microwave or on the stove, stirring occasionally, until its clear. Monoammonium phosphate, NH4H2PO4, crystallizes in quadratic prisms. The chemical is used in animal feed, plant fertilizers, and is found in some dry chemical fire extinguishers. This chemical may cause irritation and itching. If you spill it on your skin, wash it off with water. Inhaling the powder may lead to coughing and a sore throat. Monoammomium phosphate is not toxic, but its not exactly edible.

The Carbon Chemistry and Crystal Structure of Diamonds

The Carbon Chemistry and Crystal Structure of Diamonds The word diamond is derived from the Greek word adamao, meaning I tame or I subdue or the related word adamas, which means hardest steel or hardest substance. Everyone knows diamonds are hard and beautiful, but did you know a diamond could be the oldest material you might own? While the rock in which diamonds are found may be 50 to 1,600 million years old, the diamonds themselves are approximately 3.3 billion years old. This discrepancy comes from the fact that the volcanic magma that solidifies into rock, where diamonds are found did not create them, but only transported the diamonds from the Earths mantle to the surface. Diamonds also may form under the high pressures and temperatures at the site of meteorite impacts. The diamonds formed during an impact may be relatively young, but some meteorites contain stardust - debris from the death of a star - which may include diamond crystals. One such meteorite is known to contain tiny diamonds over 5 billion years old. These diamonds are older than our solar system. Start with Carbon Understanding the chemistry of a diamond requires a basic knowledge of the element carbon. A neutral carbon atom has six protons and six neutrons in its nucleus, balanced by six electrons. The electron shell configuration of carbon is 1s22s22p2. Carbon has a valence of ​four since four electrons can be accepted to fill the 2p orbital. Diamond is made up of repeating units of carbon atoms joined to four other carbon atoms via the strongest chemical linkage, covalent bonds. Each carbon atom is in a rigid tetrahedral network where it is equidistant from its neighboring carbon atoms. The structural unit of diamond consists of eight atoms, fundamentally arranged in a cube. This network is very stable and rigid, which is why diamonds are so very hard and have a high melting point. Virtually all carbon on Earth comes from the stars. Studying the isotopic ratio of the carbon in a diamond makes it possible to trace the history of the carbon. For example, at the earths surface, the ratio of isotopes carbon-12 and carbon-13 is slightly different from that of stardust. Also, certain biological processes actively sort carbon isotopes according to mass, so the isotopic ratio of carbon that has been in living things is different from that of the Earth or the stars. Therefore, it is known that the carbon for most natural diamonds comes most recently from the mantle, but the carbon for a few diamonds is the recycled carbon of microorganisms, formed into diamonds by the earths crust via plate tectonics. Some minute diamonds that are generated by meteorites are from carbon available at the site of impact; some diamond crystals within meteorites are still fresh from the stars. Crystal Structure The crystal structure of a diamond is a face-centered cubic or FCC lattice. Each carbon atom joins four other carbon atoms in regular tetrahedrons (triangular prisms). Based on the cubic form and its highly symmetrical arrangement of atoms, diamond crystals can develop into several different shapes, known as crystal habits. The most common crystal habit is the eight-sided octahedron or diamond shape. Diamond crystals can also form cubes, dodecahedra, and combinations of these shapes. Except for two shape classes, these structures are manifestations of the cubic crystal system. One exception is the flat form called a macle, which is really a composite crystal, and the other exception is the class of etched crystals, which have rounded surfaces and may have elongated shapes. Real diamond crystals dont have completely smooth faces but may have raised or indented triangular growths called trigons. Diamonds have perfect cleavage in four different directions, meaning a diamond will separat e neatly along these directions rather than break in a jagged manner. The lines of cleavage result from the diamond crystal having fewer chemical bonds along the plane of its octahedral face than in other directions. Diamond cutters take advantage of lines of cleavage to facet gemstones. Graphite is only a few electron volts more stable than diamond, but the activation barrier for conversion requires almost as much energy as destroying the entire lattice and rebuilding it. Therefore, once the diamond is formed, it will not reconvert back to graphite because the barrier is too high. Diamonds are said to be metastable since they are kinetically rather than thermodynamically stable. Under the high pressure and temperature conditions needed to form a diamond, its form is actually more stable than graphite, and so over millions of years, carbonaceous deposits may slowly crystallize into diamonds.