Why shouldn't use a ballpoint pen when marking the initial line and spots on the chromatography paper?
466214
a chromotagraphy is intended to split up artificial color into its subparts. if you use a ball point pen, the ink will also be separated. that is why you use a pencil instead. lead cannot be broken up into further pigments.
1023558
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.
795957
Use English dear.  Putting "Why" in front of an instruction does not a question make.\nI assume you are referring to a chromatogram.\nThe simple answer to the obvious question is that ink is comprised of one or more organic pigments (often phthalocyanine based) and will develop on a chromatogram just the way the applied pigment will.  This will confuse you beyond your wildest expectations.\nInstead, use pencil, which is primarily graphite (a form of carbon) which will not be carried up the chromatogram by the solvent mixture.
310782
one of your solvents is more polar than the other (in this case acetone) the substances to be separated by chromatography will move the most in a solvent mixture they are most similar to. Remember like dissolves like. So if your unknown is easily dissolved in a non-polar solvent like hexanes then a non polar solvent will move it the most on the paper. If your substance is very polar, IE. an organic acid. It will stay near the bottom of your chromatography paper, when using a non-polar solvent mixture. 9:1 ether:acetone is actually quite non-polar, you can progressively increase your solvent polarity by making multiple solvent mixtures with changing ratios 8:1, 5:1 etc.   Obviously, you must use a new piece of chromatography paper each time you run a new experiment (unless your spots didn't move at all!). The basic concept of these experiments is polarity and how it relates to separating a mixture. Remember, like dissolves like!
825466
It depends on the stage of processing.  Since you didn't specify at what stage, I'd have to say yes.\n\nBacteria populations can soar in pulp, and actually contaminate it.  At other stages, the pulp could become dispersed too fine for the quality of paper being made.  There is a standard recipe for a batch, and when something goes awry, it is easier to discard it than to figure out how to make it work.\n\nPapermaking has many variables to it, and because it is done on such a large scale to make it economical, no one would want to run the risk of wasting tens of thousands of dollars on chemicals to process a batch when the results are uncertain.  The wood pulp is probably the cheapest part of the paper.  The chemicals and processing are definitely more expensive.
823684
He used three different formulations of compounds to mark paper. \nSee U.S. Patents 160,402/403/404\nScroll sites /Select patent numbers.
806350
Could be a lot a reasons, you spilled some. If its an organic reaction you never get a 100% completion, there are always some unreacted materials left.  Thats just how organic are. if you filtered it then you lost some through the filter and and on the paper.
592082
because pencil lead (lead is a misnomer here of course) is made of graphite. graphite doesn't dissolve at all in many solvents so will not move with the mobile phase. inks on the other hand can be made from a wide variety of organic molecules and thus can run with the solvent. using an ink pen is like adding another spot to the plate.
685956
Even when the planes are pressurized, the pressure during flight is less than the pressure of the place where you left. So this difference of pressure makes the ink from your pen spill, your pen still has the higher pressure and tries to equal the pressure of the cabin releasing some ink.\nI took once an altimeter during a flight, the airport was at 600 meters and when the plane took off the pressure inside was equivalent to almost 2,000 meters (this is not the flying altitude, just the altitude equivalent to the pressure inside the plane)
15564
When you do allignment and nozzle check, the software should automatically print some test pattern. Are those test pattern printed properly?\n\nIf it does, then the printer and driver should be ok. There might be something wrong with the application you use to print your document.\n\nIf it doesn't print the test pattern properly, \n\nthen:\n1. make sure the printer power is ok, is the power ON LED lighted?\n\n2. make sure all the cables are well connected, unplug and pluggin again, then try again.\n\n3. if it is still not working, then tell us more details about what have you tried and how the printer response. so we can more specifically figure out what is the problem.
1145482
did you use a sharpie and let it bleed through??  that way you only need to write on half the pages
1023752
Tommy d. is right - don't ever sniff anything like this!!!\nno paint, no Sharpie markers, no Liquid paper, nothing like that.\nseriously!   It could cause you to burst a blood vessel in your brain.   for real.
1148702
the pen will be absorbed by the paper and fade first
802774
Modern Pens \nThe first marker was probably the felt tip marker, created in the 1940's. It was mainly used for labelling and artistic applications. In 1952, Sidney Rosenthal began marketing his "Magic Marker" which consisted of a glass bottle that held ink and a wool felt wick. By 1958, marker use was becoming common, and people used it for lettering, labelling, marking packages, and creating posters. \n\nAccording to the now defunct Magic Marker website:\n" In 1952, inventor Sidney Rosenthal developed and began marketing the first felt tip marking device. A chubby, squat glass bottle to hold ink with a wool felt wick and writing tip [this describes the unusual appearance of the first magic markers], Rosenthal named his new marking device Magic Marker because of its ability to mark on almost every surface...\n\n\nTLP
715181
The column is one of the most important components of the HPLC chromatograph because the separation of the sample components is achieved when those components pass through the column. Normally, columns are filled with silica gel because its particle shape, surface properties, and pore structure \nhelp to get a good separation. Silica is wetted by nearly every potential mobile phase, is inert to most compounds and has a high surface activity which can be modified easily with water and other agents. Silica can be used to separate a wide variety of chemical compounds,and its chromatographic behavior\nis generally predictable and reproducible.\n\nUsually, analytical columns are protected by a guard column which is an essence a disposable (or sacrificial) top of the main analytical column. The guard column is the final filter both mechanical and chemical. In addition to removing debris, it also can adsorb undesirable sample components that \notherwise might irreversibly bind and possibly change the stationary phase of the analytical and preparative columns. Although economy alone is not a persuasive argument for the use of guard columns, the need for a long stable \nlife of the analytical column to obtain reliable and reproducible results is perhaps even more important.\n\nThere are several column types, according to their function, they \ncan be classified as:\n\n a) Normal phase \n\nIn this column type, the retention is governed by the interaction of the polar parts of the stationary phase and solute. For retention to occur in normal phase, the packing must be more polar than the mobile phase with respect to the sample. Therefore, the stationary phase is usually silica and \ntypical mobile phases are hexane, methylene chloride, chloroform, diethyl ether, and mixtures of these. \n\n b) Reverse phase \n\nIn this column the packing material is relatively nonpolar and the solvent is polar with respect to the sample. Retention is the result of the interaction of the nonpolar components of the solutes and the nonpolar \nstationary phase. Typical stationary phases are nonpolar hydrocarbons, waxy liquids, or bonded hydrocarbons (such as C18, C8, etc.) and the solvents are polar aqueous-organic mixtures such as methanol-water or acetonitrile-water.\n\n c) Size exclusion \n\nIn this column type, molecules are separated according to size. Small molecules penetrate into the pores within the packing while larger molecules only partially penetrate the pores. The large molecules elute before the \nsmaller molecules.\n\n d) Ion exchange \n\nIn this column type the sample components are separated based upon attractive ionic forces between molecules carrying charged groups of opposite charge to those charges on the stationary phase. Separations are made between \na polar mobile liquid, usually water containing salts or small amounts of  alcohols, and a stationary phase containing either acidic or basic fixed sites.
785799
If you don't wish to type it, I'd suggest using a ball-point pen. Pencils are so tacky...
193404
Sharpie attack!!!!\n(but that is really the only way to do it if you don't have the printer label stuff)