In the lab u're reminded not to refill a hot alcohol lamp. Explain the reason for precausion.?
111084
Alcohol is flammable and pouring alcohol inside a hot alcohol lamp may char those beautiful eyebrows you had justdone offa you face like it never existed....
665127
eithor put it in a bucket/ milk jug or take it and when its about a quarter inch from lighting of wick left throw it up in the air. it will hopefully go up in the air, burn your hand, or explode in your face. emergency rooms cost too much, so go get some milk jug and try. have fun
126875
Could it because teh hot lamp will vaporize some of the alcohol that might then find an ignition source and flare up in your face.
67424
if the fluid is red than it is alcohol. if the fluid is silver than it mercury. either way you probably did not get enough in your blood to hurt you. If you are still concerned contact poison control or a doctor.
818868
I suspect this refers to how flourescent light bulbs generate a quasi-continuous spectrum as opposed to the discrete emission lines like other self respecting plasma discharge tubes.  \n\nHere is a website that has several pages on Flourescent Lamps:\n\nhttp://home.howstuffworks.com/fluorescent-lamp.htm\n\nThe first two or three are the ones useful to you.  Also there are several links on the last page under More Great Links that will help you in your researches.  Happy hunting!\n\nBTW: This reeks of an intro science class lab write-up question.  TAs at help desks or profs during office hours can help a great deal more effectively than something like yahoo answers, if you want to truly understand.
160219
If you are from the philippines, chances are it's methanol. It's cheap and convenient to use (in terms of burning and handling in lab classes). Just be careful. Avoid inhalation, ingestion, and skin contact. It is known to be highly toxic.
759083
to avoid  contaminating the sample
131801
When electricity is given, the bulb glows because of the power dissipated from the tungsten. This is because of the heat produced when current flows through the filament. So when the current is switched off, no current flows through the filament causing the heat not to be created. So the bulb stops glowing and light energy is not given out.\n\nSince no electric energy is given, no light energy is given out. The already produced light energy (before shutting off) i.e. the photons, are absorbed by surrounding objects so that it no longer produces light.\n\nThe photons are the smallest unit of light like cells in biology. Photons have energy in them. These energies are absorbed by surroundings.
607610
I have no idea on the exact reason (was it a committee decision?). However, 20 deg C is room temperature. This is an easy temperature to achieve and it probably really close to the temperature of the lab where they would be taking this measurement. In short, convenience
844689
i cant create a diagram, but it is usually because one holds their urine too long. Meaning, never "hold it!"
374011
It doesn't if the substance that is being tested is a liquid.  If the substance is a solid, then you need water to facilitate the interaction between the substance and the litmus.
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."
831797
No, you only breathed a little vapour in, you didn't injest any, most went onto the skin.  You don't have to worry about anything.  The bottle is warning people who drink rubbing alcohol as if it were scotch or vodka.  Unfortunately some people who are very addicted to alcohol have tried to do so and have died as a result.  Rubbing alcohol is poisonous when drunk directly through the stomach.   Other people try to get high by breathing vapours for over twenty minutes or more constantly to get high.  You can be hurt if you do this as well.  This is what the warning on the bottle is referring to.  Rubbing alcohol is perfectly safe when used to disinfect wounds., your liver can handle the small amount you breathed in easily.
763036
Because you r not dehydrated. u drink enought liquids.
891018
The white powder is a preservative.  Doesn't have anything to do with your blood alcohol.\n\nThere's no amount they're "supposed" to draw, but there is a minimum amount that has to be drawn to provide the lab with a sufficient amount to test and have enough left over for the defense to have re-tested.  What that amount is will vary by state law, lab policy and maybe even prosecutor's policy.
874660
This is sort of a guess, so you may wish to verify it for sure.  I know, for sure alcohol, has a much lower freezing point.  So if you put cells in a 50% alcohol solution, the cells would require a lower temperature for freezing.  \n\nYour question is not about freezing cells Per Se, so maybe this extra tidbit will be more helpful:  \n\nI have put cells in 70% alcohol solution and maintained them in a freezer.  I did this because I wanted to preserve the antigens present on the cell membrane.  I believe you would have to do this for an hour or so, in order for best preservation.  But you would probably need to use the cells in the follow-up assay (for me it was flow cytometry) within a 24 hour period.\n\nWhen I have deep freezed cells for long term storage, I did it in DMSO.  That's the standard method.\n\nIn short, keeping cells in 70% ethanol will preserve antigen found on cell surface membrane.\n\nI wish I could speak for chloroform, but nowadays people rarely use it due to its high toxicity and high flash point. \n\nHope this helps.
1130741
On Preperation H, Do Not Ingest.  WTF?!  What idiot actually did that to get that warning label?!  On a hair dryer box, Not a portable heater....Gee ya think?!