What compound did Edison find to chemically mark paper for telegraph messages?
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He used three different formulations of compounds to mark paper. \nSee U.S. Patents 160,402/403/404\nScroll sites /Select patent numbers.
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Yes. These are usually refered to as latent prints.\nPaper acts as a blotter, absorbing skin secretions when touched.\nWhen the paper is exposed to chemicals that react with the skin secretions they cause the print to become visible.
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Hmm. . its pretty rare stuff so you are not going to hand out samples\nSince it was once used in lasers you could start your presentation with a laser light show, or just a simple laser pointer\nPresent the information chronologically, show how and why it was discovered (it started as a blank square on the Periodic Table of the Elelments) talk about it uses and why it was replaced\ngood luck
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The spark in the presents of oxygen starts a chemical reaction with the paper that breaks the molecules apart releasing energy.
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Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who developed many devices which greatly influenced life in the 20th century. Dubbed "The Wizard of Menlo Park" by a newspaper reporter, he was one of the first inventors to apply the principles of mass production to the process of invention, and can therefore be credited with the creation of the first industrial research laboratory. Some of the inventions credited to him were not completely original, but alterations of earlier patents (most famously the light bulb), or were actually the work of his numerous employees. Nevertheless, Edison is considered one of the most prolific inventors in history, holding 1,097 U.S. patents in his name, as well as many patents in the United Kingdom, France, and Germany.
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A normal chemical battery or pencil cell converts the chemical energy stored in it to electrical energy.The reactions between zinc and copper sulphate produces the reqiured energy.\nAbout stryroform...well frankly speaking I dont have the slightest idea...but u can try \nwww.answers.com\nmaybe it will help u
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Talk about how paper is made.
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Lead acetate (lead(II) ethanoate) is used to detect the presence of hydrogen sulphide, H2S. A strip of paper is soaked in the solution, and held in the stream of the (smelly) gas. If the paper turns black (with lead sulphide, PbS) then hydrogen sulphide was present.\n\nPb2+ + H2S ---> PbS + 2H+\n\nThis used to be frequently done in UK schools, but no longer.
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I believe it was a couple of 3M employees. Spencer Silver invented the weak glue that is used on the Post-It, but couldn't find a use for it. Then later Arthur Fry stumbled on the idea to use it to mark pages in his hymm book.
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invented by Thomas Edison in 1879\n\nheres 833,000 sources
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Ingredients:\nWater \nFlour (one part flour to one part water) \nStrips of Newspaper, about 1 inch wide \nchicken wire (form into the shape of a volcano, this will be the base and hold the papermache in place while it is drying)\nDirections:\nMix flour and water in a large bowl (2 cups of each is a good amount with which to start) until it makes a smooth paste. Dip in the newspaper strips, one at a time, remove the excess paste from your fingers and lay the coated newspaper on the form to be papier mâchèd. Smooth out the wrinkles and continue to place coated newspaper over the surface until completely covered. When the surface has totally dried, paint your own design using acrylic or poster paint.
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Paper, thin sheets of compressed vegetable cellulose fibers. Paper is used for writing and printing, for wrapping and packaging, and for a variety of special purposes ranging from the filtration of precipitates from solutions to the manufacture of certain types of building materials. Paper is a necessity in modern civilization, and the development of machinery for its high-speed production has been largely responsible for the increase in literacy and the raising of educational levels of people throughout the world.\n\n\nThe basic process of making paper has not changed in more than 2,000 years. It involves two stages: the breaking up of raw material in water to form a suspension of individual fibers and the formation of felted sheets by spreading this suspension on a suitable porous surface, through which excess water can drain.\n\nIn making paper by hand, the raw material—straw, leaves, bark, rags, or other fibrous material—is placed in a vat or trough and is pounded with a heavy pestle or hammer to separate the fibers. During the first portion of this operation, the material is washed with running water to remove impurities, but after the fibers have been sufficiently broken up, they are kept in suspension, and the water in the vat is not changed. At this stage the liquid material, called half stuff, is ready for the actual process of papermaking. The chief tool of the papermaker is the mold, a reinforced sheet of metal mesh having either a square mesh pattern, called a wove pattern, or a pattern of more widely spaced longitudinal wires held together with smaller transverse wires, called a laid pattern. The mold pattern imprints itself on the finished sheet of paper, and thus handmade papers that are not given special finishes are identified as wove or laid papers, depending on the style of mold that is used in their making.\n\nThe mold is placed inside a removable wooden frame called a deckle, which forms a low rim around its edge. The papermaker dips the mold and deckle into a vat containing the half stuff; when the mold and deckle are removed from the vat, the surface of the mold is coated with a thin film of fiber-water mixture. The device is then shaken forward and backward and from side to side. This shaking has two effects; it distributes the mixture evenly on the surface of the mold and causes the individual fibers to interlock with those adjacent, giving strength to the sheet. While the device is being shaken, much of the water from the mixture drains out through the mold mesh. The device, with its formed sheet of wet paper, is then laid aside until the paper is sufficiently cohesive to permit the removal of the deckle.\n\n\nAfter the deckle has been taken from the mold, the mold is turned over and the sheet of paper is laid smoothly on a sheet of woven woolen cloth, called a felt. Another felt is laid over the sheet of paper, and the process is repeated; the process of placing the paper between two felts is known as couching. When a number of sheets of paper have been interleaved with felts, the entire pile, called a post, is placed in a hydraulic press and subjected to a pressure of 100 or more tons, expelling most of the water remaining in the paper. The sheets of paper are then separated from the felts, stacked, and pressed. The process of pressing the stack of paper is repeated several times, and each time the stack is built up in a different order with the individual sheets in different positions relative to one another. This procedure is called exchanging, and its repetition improves the surface of the finished paper. The final stage in papermaking is drying. The paper is hung, in groups of four or five sheets, over ropes in a special drying room until its moisture has almost completely evaporated.\n\nPapers that are to be used for writing or printing with ink require additional treatment following drying, because without such treatment the paper would absorb ink and yield fuzzy lines or impressions. The
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n-hexanoic acid\n\nThere are a LOT of compounds with that chemical formula.  Check chemfinder.com for more.
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Weel, it was used to hiode things in plain site...for example. When threated with special subtances, or under special light the invisible ink becomes visible. So you can send a hidden message in a letter that, in appeareace, contains nothing special. Hope this helps :)
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Lithimus paper is used to gage pH level.  An acid turns red lithimus paper blue and a base turns blue lithimus paper red.
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I think it is a mechanical technique.  The powder simply sticks in the oils from the skin left behind on the surface. I am not up on modern techniques, but perhaps some chemical reaction between the powder and some treated paper allows investigators to make copies of the prints.\n\nElectrophoresis is a technique where an applied electric field causes charged molecules to move through a medium; usually a gel these days but paper used to be used.  Larger molecules tend to move more slowly, and more highly charged molecules will move more quickly, so you can separate compounds.  I don't see how this might be used in fingerprinting.
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Paper chromatography is a modern method used separate mixtures. Paper chromatography uses paper as the stationary phase and a liquid solvent as the mobile phase.\n\nYou will use paper chromatography to test food colorings to see if the color results from a single dye or mixture of dyes. If you cannot get food coloring you can use colored felt pens or other water soluble coloring pens. Your exercise is simple but uses very essential principles. An optional part of the activity is to check a household product for the presence of the same dyes that are in food coloring.\n\nThe technique relies on the idea that the solvent and the paper both have an attraction for the components in a mixture. The solvent creeps along the surface of the paper. If a material is placed on one spot on the paper and is soluble in the liquid solvent, the material will be dissolved when the solvent moves over it. The material will move along with the solvent. Each compound in a mixture will have its own characteristic balance of attractions to solvent and to paper, so all will not move at the same speed. Eventually this difference in speed will separate the compounds.\n\nIn paper chromatography when the conditions are kept constant, a particular compound always travels a fixed percentage of the distance traveled by the solvent front. The ratio of the distance the compound travels to the distance the solvent travels is called the Rf value. The symbol Rf stands for "retardation factor" or "ratio-to-front". It is expressed as a decimal fraction. When the conditions are duplicated, the same average relative positions will turn up for the solvent and solute; thus the Rf value is a constant for a given compound. The Rf value is a physical property for that compound. The Rf value is useful in identifying compounds, but other properties should be used in combination with the Rf value to confirm compound identification. Since it is difficult for different laboratories to exactly duplicate conditions for a chromatography experiment, Rf values are more useful for comparisons within one lab than for comparisons of data from different labs.\n\nSubstances that are not colored can also be separated by chromatography. They are detected using ultraviolet or black light. These substances appear to glow in the dark.