Why does a lead acid battery give an inprint on a cement garage floor.?
831735
Reaction between the battery and traces of iron in the concrete. Electrolyte level may have been low already.
631579
2 electrodes and a battery
616514
Generating static electricity.
370125
you are almost right, electrical ground is allways relative to a higer potential source like a live wire and the current flows toward ground from the higer source, when you ar isolated (you have rubber shoes, you have a high resistance in the way of the current), there still a current flow, but it is so small (nano amperes) that you body cant feel it
1186885
I'm taking your question literally:  the lead (Pb) is on leads of a dual in-line package IC for through-hole applications, and the quantity of Pb is just the amount used for 'tinning' to promote solderability, and these are not surface mount packages.\n\nAlso, I'm assuming that:\nYou've confirmed the law applies to you (this is not networking equipment).\nYou've applied for and don't qualify under one of the exemptions.\nYou're shipping TO the EC countries.\nThese aren't cheap 'jelly-bean' devices you can just throw away.\nThey are plastic rather than ceramic packages.\n\nThere are three ways to remove the lead:\n1) Mechanically,\n2) Chemically (with acid),\n3) Solubility.\n\n1) Mechanical removal is usually not practical because of static electricity considerations, and, you can't get to all sides of the device.  It should be mentioned, however, the IC leads probably could withstand bending out flat (like gull-wings) so that you could get access to both sides, and use mechanical-abrasive methods to remove the lead (electronic grade baking soda abrasive blasting techniques for example, or residue-free CO2 ice blasting, mechanical sanding, etc.).   Depends on the static sensitivity of your device and especially how you 'ground' the device in a custom-built enclosed fixture to eliminate static damage.  Is labor-intensive, but doable to salvage an expensive device - suitable for low volumes - can be subcontracted to local shops for 'rework', but you'll have to spend time confirming that the ***very strict*** anti-static measures are implemented and adhered to on the shop floor.  I don't think any post-rework electronic testing is really going to catch static damaged parts (some will only be 'wounded' and will fail prematurely - short-term testing won't find this), so your only recourse is to avoid damage in the first place.  Bead-blast residues are relatively small and inexpensive to capture and dispose of.\n\n2)  Chemical methods would take advantage of the solubility of lead in certain liquids at room temperature (i.e, acids).  FUNDAMENTAL PROBLEM:  aqueous-based solvents WILL be absorbed into the plastic.  Further, acidic ions will remain trapped in the crevices by capillary action and migrate over time by diffusion directly into through plastic to the electronic device where corrosion could occur.  So the requirements for dissolution by acid are:  Acids that would eventually cause device failure are excluded (this eliminates HCL due to chloride migration to the wirebonds and subsequent corrosion),  acids that are difficult to rinse are excluded (sulfuric acid is notoriously difficult to rinse).  Further, it would only make sense to encapsulate the epoxy IC package in a protective covering to isolate the acid from the plastic packaging in the first place (thus tooling and extra labor expense is involved).  Acetic acid is a weak organic acid that *might* be usable, in that its diffusion through plastic is lower due to the larger molecule size compared to HCl.  You'd have to check acetic acid against solubility of lead vs. its compatibility with gold, silicon, aluminum, copper, epoxy used in IC manufacturing.  THEN you'd need to 'tin' the leads with some other metal (another expense).  After rinsing, the plastic packages would need to be 'baked' to drive off the moisture (and hopefully acetic acid residues if baking temp is above boiling point of acetic acid) - this must be done in a oven specially designed for removing humidity with a rechargable dessicant (an ordinary oven won't get the dew-point low enough; you need -80°F dew point or thereabouts), and you'd need to confirm by laboratory methods the acetic acid was gone.   Acetic acid is so slow acting that I don't think you'd want to wait around for it to work (time is money), but whatever the candidate acid, it would be one that you could remove the t
726552
Probably PVC.....it's pretty inert and resistant to acid or, in your case, base.
457188
There are Lead Acid type, sealed batteries, Nicad batteries etc, describing all here is difclt, try web sites like wikepedia etc
249044
"Their intention is to try to make them last longer prior to use. I think everybody has had the experience of putting a bunch of batteries in a flashlight and then putting it in the trunk of their car, and they go back when they need the flashlight and it doesn’t work. Because just on standing, batteries actually deplete themselves. So the idea is that there’s a certain amount of chemical inside—it’s a chemical reaction that’s taking place in the battery—and the chemicals basically get used up. They basically just run out of active material.\n\nMost chemical reactions are affected by temperature, and the lower the temperature the slower the chemical reaction. So what people are trying to do is slow down the self-depletion mechanisms of the batteries by keeping them cold.\n\nIn general, it does extend the battery’s life. Whether there’s a significant difference that would be measurable to the consumer between room temperature and a refrigerator.... To be honest, I don’t know. But in general it does work—that if batteries are kept cooler while they’re not in use it will extend their shelf life.\n\nSo then what about the freezer? Is it even better?\n\nI think one would have to be careful about that. Because it’s the freezer, and the freezer is quite cold. Depending upon the type of batteries, you can actually freeze some of the internal components, and that would not be good. So probably the refrigerator is a safe bet and it will improve things a little bit.\n\nWhat if there are batteries that you’ve been using but will not use again for a while. Would placing them in the fridge in the meantime help at all?\n\nYeah, if you plan on storing them for a long time, it probably would. I think typically people put them in the refrigerator before use. Certainly people should not try to use the battery or activate the battery while it’s cold. It may not work very well. But if they let it warm up before they use it, it should help. \n\nWhat about batteries that are starting to run low?\n\n\nNo, that won’t help. When they start to run low they’re basically used up."
178279
Something is out of place or there is a fragment of paper left in there somewhere.  One or more sensor is not happy.
601853
Battery tester is a thin film of material which changes its color when current/voltage is applied. The thin film of material  is formed into a strip pattern which is then coated with conductive material at the end of the strip. By adding supply at the end this particular material changes its color.\n\nYou can open and see a DURA CEL Battery
926443
IF THIS COMPAQ IS  NEWER THAN 3OR4 YRS  IT IS SIMPLE.  THAT BATTERY THAT YOU ARE SPEAKING OF  IS ABOUT THE SIZE OF A NICKEL  ?  THAT BATTERY IS CALLED A CMOS  BATTERY .FIRST  OFF TRY CHANGING YOUR TIME SETTINGS IN CONTROL PANEL.I`LL  ASSUME ITS A DAYLIGHT SAVINGS ISSUE .  WHEN THAT BATTERY GETS OLD  OTHER THINGS WILL HAPPEN B4 YOUR CLOCKGOES  AWRY   CMOS  STANDS FOR  [COMPLIMENTARY  METAL  OXIDE SEMICONDUCTOR] YA I KNOW    WHILE YOU ARE  REMOVING CMOS  1ST  DISCONNECT POWER  2ND  USE A  PLASTIC  DEVICE TO GENTLY REMOVEIT. 3RD  WHILE  YOU ARE  IN YOUR CAGE MAKE SURE  ONE OF  YOUR HANDS IS TOUCHING THE METAL PART OF THE CAGE TO DISCHARGE THE BODIES STATIC ELECTRICITY.STATIC DISCHARGE CAN FRY YOUR WHOLE SYSTEM RARELY .THE BATTERY   IS PROBABLY A CR2032. ENERGIZER
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.
489342
A VRLA battery is a basic lead acid battery and an internal between one or a number of cells will render it useless.  An internal short will prevent that cell from working (will produce no EMF) and so the output voltage of the battery will be reduced by the amount that would be given by that cell.\nBattery no good I'm afraid and no chance of recovering it.\nP.
399371
Basically, when you rub two certain materials, you will create static electricity, which is named that way because the charges do not _flow_, i.e. there is no current.\n\nNot so basically, but still very primitively, there exist two forms of material: ones that "likes" to "steal" electrons, and ones that "likes" to "give" electrons. Whenever these two are put next to each other, the electrons "jump" from one substance to the other, causing a potential difference, and possibly a spark (if the potential difference is high enough).\n\nRubbing two such materials does not cause this effect. It is a common misconception; when you rub two things you are simply increasing the surface area of contact between the two such substances, thereby creating a more noticeable effect.\n\nand the check spelling button screwed up some of my spelling. fix it yahoo! people, please. especially with the word 'effect' which was changed to 'effectt' and the plural of some words.
180743
It cause u nothing dear. It works on the battery. It helps u by noting dates, battery power etc, Ok na
368255
No , Because inside the battery is acid and this acid makes energy.When the battery is flat the acid is dry so the battery can't make energy.
196083
You should remove the batteries because even if they are not used, the chemicals in the battery can eat through the housing and damage the device.\n\nAlso, the chemicals in the batteries have a "shelf-life" where they will react slowly even if there is no electrical discharge.