How one can distinguish between amorphous and noncrystalline materials?
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amorphous is without form: ant. crystalline\ncrystalline is having regular molecular structure: ant. amorphous\namorphous is synonymous to non-crystalline. The two terms are interchangeable and not dissimilar.
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go to encarta.msn.com and search for keys mass/solid structure, surface Structure
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http://chemistry.allinfoabout.com/features/nonmetals.html
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Peter B has it right -- atomic absorption will do elemental analysis.\n\nAtomic emission spectroscopy is another tack, though a bit more challenging.
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Distinguishing between the two mineral groups with the microscope can be accomplished quickly by crossing the polars, with the following being obvious:\n\nAll isotropic minerals will appear dark, and stay dark on rotation of the stage. \nAnisotropic minerals will allow some light to pass, and thus will be generally light, unless in specific orientations. \nWhy are isotropic materials dark?\n\nIsotropic minerals do no affect the polarization direction of the light which has passed through lower polarizer; \nLight which passes through the mineral is absorbed by the upper polar. \nWhy do anisotropic minerals not appear dark and stay dark as the stage is rotated?\n\nAnisotropic minerals do affect the polarization of light passing through them, so some component of the light is able to pass through the upper polar. \nAnisotropic minerals will appear dark or extinct every 90° of rotation of the microscope stage. \nAny grains which are extinct will become light again, under crossed polars as the stage is rotated slightly\n\nAnisotropic minerals differ from isotropic minerals because:\n\nthe velocity of light varies depending on direction through the mineral; \nthey show double refraction. \nWhen light enters an anisotropic mineral it is split into two rays of different velocity which vibrate at right angles to each other.\n\nIn anisotropic minerals there are one or two directions, through the mineral, along which light behaves as though the mineral were isotropic. This direction or these directions are referred to as the optic axis.\n\nHexagonal and tetragonal minerals have one optic axis and are optically UNIAXIAL.\n\nOrthorhombic, monoclinic and triclinic minerals have two optic axes and are optically BIAXIAL\nbasically the ones light can travel thruogh are isotropic, like garnets,emeralds,quartz.\nminerals light does not travel through are anisotropic.
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Try   http://www.insitu.de/materialdatabase/materialdatabase_2_4e.html
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Recognize the patterns that occur in the table; it is not called "periodic" without reason. It is also helpful to associate each category with a familiar elemet, for example, silicon with metalloids, as it makes one familar with the properties of that group.
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Glass is an amorphous solid, meaning it does not have a crystalline structure, like most solids. The belief that it flows is due mainly to the fact that old windows appear to be thicker at the bottom than the top. This is because they were actually installed thicker at the bottom than the top. The predicted relaxation time for glass is 10^32 years.
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You can either look it up or determine it experimentally.\nI cant get much more specific without additional details.
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There are many types of glass. Different mixures creates different optical densities. These different optical densities will make the refractive index of glass vary. However, in GCSE 'O' Level, the refractive index of glass is usually 1.5. (hope this helps you)
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glassy - cools very fast; extrusive igneous rocks; no crystals; includes obsidian & pumice\nfine-grained - cools quickly but not as fast as above; crystals don't have time to grow large; crystals are generally all the same size\ncoarse-grained - larger size crystals; usually intrusive igneous rocks; crystals are usually uniform\nporphyritic - has two different & distinct crystal sizes that resembles a "chocolate chip cookie" as I tell my students; the larger grains are fewer than the smaller ones
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Plastic vs. Glass\nfirst off it isn't too fair to compare plastic to glass. You're comparing a category of materials against one single material. Plastics have almost an infinite range of properties where as glass has one set of properties. There are some plastics such, as acrylics, that behave very similarly as glass with respect to impact strength, clarity, etc. And there are some plastic that behave nothing like glass. Such as polyurethane, very ductile and rubbery even. \nTo conclude, depending on the plastic there can be many differences between plastic and glass, or they can be quite similar.
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Glass:\namorph structure (not cristaline)\ncasant\nan melted mixture of Na2O, SiO2, K20\ntransparent\ninsipide\n\nSalt:\ncristaline structure - cubic system\nNaCl - natrium chloride\ntranslucid\nsalty taste
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Solid and in solids Diamond.\n\nSecond  Alummina and titanium carbide.
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A crystal shape is the arrangement of the molecules in a compound...carbon fiber is a crystalline structure since it is arranged in a pattern when observed under a microscope. Glass, however isn't a crystalline structure, and will be disorganized. Also, a quick fact is that glass will always be in motion due to it's non-crystalline structure. The bottom of a pane of glass will be thicker than the top after many years :) A high melting point means that it will take more heat to induce a state change... Metal is frozen at room temperature and has a high melting point, as opposed to water, which has a melting point around 33 degrees farenheit.
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Metals, Nonmetals, & Metalloids\n\nMost periodic tables contain a stairstep line which allows you to identify which elements are metals, nonmetals, and metalloids. Following are descriptions of each of the three types of materials.\n\nMetals\n\nMost elements are metals. 88 elements to the left of the stairstep line are metals or metal like elements.\n\nPhysical Properties of Metals:\n\nLuster (shininess) \nGood conductors of heat and electricity \nHigh density (heavy for their size) \nHigh melting point \nDuctile (most metals can be drawn out into thin wires) \nMalleable (most metals can be hammered into thin sheets) \nChemical Properties of Metals:\n\nEasily lose electrons \nCorrode easily. Corrosion is a gradual wearing away. (Example: silver tarnishing and iron rusting) \nNonmetals\n\nNonmetals are found to the right of the stairstep line. Their characteristics are opposite those of metals.\n\nPhysical Properties of Nonmetals:\n\nNo luster (dull appearance) \nPoor conductor of heat and electricity \nBrittle (breaks easily) \nNot ductile \nNot malleable \nLow density \nLow melting point \nChemical Properties of Nonmetals:\n\nTend to gain electrons \nSince metals tend to lose electrons and nonmetals tend to gain electrons, metals and nonmetals like to form compounds with each other. These compounds are called ionic compounds. When two or more nonmetals bond with each other, they form a covalent compound.\n\nMetalloids\n\nElements on both sides of the zigzag line have properties of both metals and nonmetals. These elements are called metalloids.\n\nPhysical Properties of Metalloids:\n\nSolids \nCan be shiny or dull \nDuctile \nMalleable \nConduct heat and electricity better than nonmetals but not as well as metals
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Glass is made from silica and sand, heated at very high temperatures.  Different colors come from adding different metals and other elements.