John Cuthber

Perhaps the easy answer is that 0/0 can't be 1 because it is 42 0/0=42 Multiply both sides by 0 0=42*0 Simplify 0=0 Perfectly correct. Unfortunately it works for 0/0= e, or 0/0= -3i or any other number. Since the ratio of zero to itself can give any answer you like it's fair to say that 0/0 is indeed 1, however it's also 2, 0 or whatever. That's why it's undefined.

Tannic acid is a weak acid, in the stomach it will be fully protonated and not in any position to react with basic drugd (which will also be protonated). It's not a stimulant to any measurable extent and I doubt that much of it is ever absorbed by the body. One of the components of tannin, specifically from red wine, resveratrol is know to act as an anti oxidant- this may be why drinking red wine in moderation is associated with longer life. Many vegetables and fruits contain significant amounts of tannic acid so it would be tricky to get a balanced diet that avoided them. The stuimulation from tea and coffe comes from methyl xanthines like cafeine.

The by product of the reaction of ammonia and iodine is ammonium iodide. Very hygroscopic, but it might have been responsible for the crystals in very dry weather. Was the "iodine" in the bottle crystals or was it a solution? If it was a liquid then it was almost certainly in solution with KI which would explain the crystals.

I should knoew better than to try to answer this 'cause I'm not a mathematician but here goes. I guess by "best" you mean with a determinant that is as far from zero as possible. The determinant of a matrix coresponds to the volume of the object produced by that matrix operating on the unit cube, and that will be maximised (I think) if the vectors are as big as possible and as near normal to one another as possible. Certainly , if 2 of them are colineear you will have problems. Of course, with a decent computer, checking all the combinations wouldn't take long.

"you can clearly see the UV light coming from it." A clever trick. That light is from the innert gas filling, rather thasn sodium. Until the Na gets warm there's no Na vapour in the tube to emit yellow light.

The equation involves the ratio of the concns. That ratio goes from (practically none : lots) to (lots : practically none) as you pass the endpoint. What's the ratio at the endpoint?

What do you mean by "pure electricity alone will actually give a Violet to UV light 1`st, Then with the addition of heat you`ll get yellow."

If your solution is much more acid than the indicator then the indicator will be entirely in the acid form. If your solution is much more alkaline then the indicator will be in the base form. (Roughly) how much of each is present when you are just at the end point? From that and this http://en.wikipedia.org/wiki/Henderson-Hasselbalch_equation you should be able to calculate the answer you need.

I guessed that, but sea salt is still pretty much salt. The other components are in relatively small amounts, next on the list of elements in seawater is magnesium, and there's more than 10 times as much NaCl as Mg. Strictly we ought to worry abot the temperature and the particular source of teh water, but "About 36%" is probably as good an answer as any.

Tea is generally drunk hot. That might upset some medication, particularly "time release" preparations. Incidentally, re. "When taking medicine we usually drink warm water" I don't know about you, but if I want an aspirin, I'm not going to waste time warming water. It will be near 37 C pretty soon anyway.

Part of being a scientist is clear communication. Where were you?

I'ts a while since I rode a bike but I remember that even a slight headwind made a lot of difference to how easy it was to cycle. On the other hand, the bearings on a bike are pretty good so I guess that the effect of wind resistance dominates. The fact that they are riders on bikes isn't very important if you are only looking at wind resistance. The problem is the same as two objects dropped through the air. In that case, the small object will fall slower than the big one if the objects are otherwise similar. As evidence I submit that fog doesn't fall out of the air quickly, but rain does. The small drops in fog are analagous to the smaller rider, the bigger raindrops act like the bigger rider.

I'm not sure the question is meaningful. Seawater is saturated with, for example, sand. If you concentrate it slightly it will be supersaturated and silica will crystalise out. If you are trying to get salt to crystalise then YT's answer must be pretty close, even allowing for other things in the water.

To some tiny degree when you walk through a door your path may (and probably will) deviate slightly from a straight line.

This sort of thing? http://www.sigmaaldrich.com/catalog/search/ProductDetail/ALDRICH/Z530212 You might want to look at a sandblaster/ shotblaster. They are a lot more robust than the bags but cheaper than a proper glovebox. http://cgi.ebay.co.uk/SANDBLASTING-SANDBLASTER-AUTO-PARTS-CLEANING-CABINET_W0QQitemZ180264257776QQihZ008QQcategoryZ22662QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

"Blue screen of death" anyone?

"John, apply these groupings to special magnetic properties with faraday counter-rotating disks and come back and comment as though you are actually basing your observations on real world experience." What groupings? What special magnetic properties? What, when it's at home, is a Faraday counter-rotating disk? I may not be in the real world, but at least I'm not in the business of inventing random phrases. Anyway, let me know if anything changes about the periodic table being based on the arangement of the electrons and having nothing much to do with the properties of the nuclei. If you can do that without the personal attack it's more likely to get read. In the meantime, for the benefit of those who wonder why I spend my time replying to things like this, have a look here. http://xkcd.com/386/

The word "very" has little to do with it. What we are talking about is that fact that from most people's point of view buying NaOH from the shop is easier than making LiOH by opening up batteries and reacting the Li with water. "it's very strong compared to anything this fellow is likely to have come across if he is forced to extract lithium from batteries rather than just buy it." No it's not- it's pretty much as strong a bas as NaOH. The guy may or may not know that he can buy roughly as stong a base from the shops rather than messing about with Li batteries- but that's his problem. He will have come across NaOH- possibly as you described it. Possibly like I buy it, clearly labeled with, I grant you, not its IUPAC aproved name, but hardly some obscure brand name. BTW, If someone knows how to shrink that image to a bit less overpowering please feel free.

I think this "An object heading straight for us is harder to detect than one that will miss, because it won't move much with respect to the background stars. — It will look like one." is true in principle, but how can an object head directly towards us when we are moving?

In solids you can measure the size of the molecules to great accuracy by Xray diffraction. If all the molecules are the same then you can say that their size is the same as the separation between one and the next in the lattice. If you look here http://www.lsbu.ac.uk/water/ice1h.html you can see the dimensions of the lattice of water molecules in ice crystals measured to 5 digits.

"YOU know that oven cleaner is NaOH, he might not. " Actually, I was talking about drain cleaner- the stuff I haver is labeled as "Caustic soda" and it lists the ingredient as 98% sodium hydroxide. It seems to me that NaOH is easier to get than Li.

"The poisonous and harmless pills are identical in every way except that the harmless ones weigh 1.1 g and the poisonous ones only weigh 1.0 g. " That seems odd- surely one important distinction (in addition to the difference in mass) is that one set of pills is toxic and the other isn't. Did you mean that the pills seem identical... Anyway, if you take one pill from the first bottle, two pills from the second bottle and so on, put them all together on the scale and weigh them. If the first bottle's not the poison you get 1.1+2+3+4...=45.1 g . If it's the second bottle you get 1+2.2+3+4+...=45.2g The difference between the mass and the nearest integer below is the number of the bottle with the non poison pills.

Why? If I drive a cap past some point there's a (single) time when the front of that car passes that point. The car doesn't need to stop. What's the difference?

I think it must all be a scam anyway. You can't have a large hadron colider because there are no large hadrons- they are all tiny.

"any effect would not be noticable and the conditions under which it would need to occur would result in the cats being dead" Surely if it killed the cat this woulds be noticable.