jdurg

Hmmm. Interesting. To me, the whole string-theory/anti-string-theory debate has seemed pretty similar to the Phlogiston/Anti-Phlogiston debates that occured in chemistry a long time ago. The Phlogiston theory was developed without any real proof of existance and was constantly changed to meet whatever experimental observations were found. It wasn't until absolute conclusive proof that it was wrong was discovered that people began to abandon it. Still, some scientists held strongly to their beliefs and never accepted any other theories. I think a similar thing may be happening here. I've always thought that the quantum level of science was always very intersting, but always made my head hurt. lol. I am very fond of radioactivity and what causes it, and would love to see research done so that someday we could have a way to safely dispose of our nuclear waste that is constantly piling up.

I found it funny how early last week the local weather people said that at this point in the winter our area had half as much snow as we had last winter at this time. Then this weekend over 2 feet of snow fell on Saturday night. Now I think we're all caught up.

Some bad element name puns to help you remember their symbols: A-U! Get away from my gold. C-U Later Copper! N-A-way you look at it, sodium's pretty freaking reactive. Don't forget to P-B for you go to lead!

I would guess that it's because the electron density is concentrated around the Nitrogen atoms and not spread out evenly amongst all the 'ring' atoms like it is in benzene. (Since in benzene all the ring atoms are carbon atoms, so the electron density is evenly spread out which results in no 'charged' areas). In the borazole molecule, the electron density will be a bit higher around the nitrogen atoms since nitrogen is more electronegative than boron. This will result in charged areas of the molecule which will destabilize it overall and lead to a higher reactivity. In addition, looking at the position of both Boron and Nitrogen on the periodic table, the nitrogen atom would like to 'obtain' 3 electrons in a bond while boron would like to 'donate' them. In the borazole molecule, both the boron and nitrogen atoms have 4 bonds in a sense. This isn't an enegertically favored state for either of the atoms, so they would rather react with something and obtain that optimal number of bonds. (If I am incorrect, please somebody correct me since I'm just making this basis on logical assumption based upon what I know. O-Chem was always a bit of an iffy subject for me. )

I would tend to agree with Primarygun. The only place that the hydronium ion exists is in an aqueous solution, and in an aqueous solution CaO forms Ca(OH)2. While it's not very soluble in water, as it does dissolve it reacts with the hydronium ions forming a calcium salt and water. This pushes the equillibrium further towards the right and allows more calcium hydroxide to dissolve. Therefore, there is really no difference between calcium oxide and calcium hydroxide. I believe the one place where CaO is a bit better than Ca(OH)2 is the speed with which is will raise the pH. With the CaO it will probably take a bit longer and be more gradual of a pH adjustment since the oxide has to dissolve in water first before it can take on the hydronium ions, while the hydroxide can just take on the hydronium ions immediately when it's surrounded by water. Therefore it will be effective for a slightly longer period of time.

Yeah, that's a ugly little course called 'Physical Chemistry'. <cowers in the corner in fear>.

Yeah, NO2 and N2O4 aren't something you want to be ingesting in large quantities. However on the scale that you'd probably be doing this at, the amounts shouldn't be all that great. You'll know you're making the gas if you see the brown color of N2O4, or if the reaction area smells like you're stuck in traffic.

The 'temporary' names given are assigned by IUPAC. Until a formal name is decided upon, they use a systemic latin system. For element 115, for example, they would use Ununpentium (115-ium in Latin). So this is why many of those elements appear to have similar names, however the temporary naming does make sense. I remember when I first started chemistry back in the mid-90's, a VAST majority of the elements past the actinides had these temporary names. Kind of makes me feel old seeing these official names coming out.

Yeah, the brackets pretty much mean 'this element doesn't occur naturally, but the weight we have here in the brackets is for the isotope that's easiest to make'. The weights of the other elements are calculated based on isotope percentages as mentioned earlier. Scientists will take purified samples of elements and run them through a mass spec. They are then able to see the different isotopes and their masses. With that information they can calculate the atomic weights. As the instrumentation and sample sizes increase, the weights become even more accurate.

With H2O2 and KI, I can believe that a yellow foam formed. The KI catalyzed the decomposition of H2O2 into oxygen gas and water. A little bit of iodine will be formed, and iodine is VERY slightly soluble in water. If you take some iodine crystals and put them into some warm water, the water will turn a yellowish-brown color from the little bit of I2 that dissolved.

Have any of you ever been in a chemistry lab or a store-room and saw something lying around that just made you go at the sight of it? It's happened to me a couple of times. High School: A half gallon of bromine in the chemical room. Yeah it was sealed and heavily wrapped, but still, a half gallon? 125 gram lump of white phosphorus. Various unlabelled chemicals of varying colors which we were never able to identify and too nervous to touch. College: Old biology closets where VERY old specimens were in jars of picric acid which had evaporated into a dangerous yellow crust. (Bomb squad had to come in and remove the jars and subsequently detonate them). Platinum/palladium beakers and trays lying around with various other 'scrap' metal. (Boy I wish I could have gotten one of those ) 1 kg jars of NaCN and KCN stored around other thiocyanate salts. VERY old and encrusted bottle of perchloric acid in the waaaaaaaaaay back of a fume hood cabinet. And perhaps the scariest one I ever came across was in my toxicology lab. There were some old bottles and jars of chemicals in the back shelving area of the lab. Some of which were still used, and many of which had just been there for quite a while. I noticed one small bottle on the bottom shelving area which had an incredibly bright green substance in it. The substance looked like a rock candy but was almost neon green in color. The bottle was about 3 inches high and an inch in diameter. The neon green crystals inside filled it up about 3/4, and there was a fine powder of it that filled up the bottom 1/4 of the bottle. I got closer to it and looked at the label: Uranyl Acetate!!!!!!!!!! I quickly moved away from that area. Not only is that stuff incredibly toxic due to its high solubility, but it's also incredibly 'hot' in terms of radioactivity because of the massive quantity that was there. I can only imagine what would happen if the jar fell off the shelf and shattered on the floor.

It decomposes in a fast chain reaction fashion resulting in the production of numerous gas molecules from the solitary solid molecule. I.E. it goes KABOOM!

lol. I know that feeling. My high school chemistry teacher was great. She let me come into the lab during my study hall and just go through the volumes upon volumes of chemistry demonstration books that she had and test some of them out. She also gave me free roam of the chemical supply closet. (There was some scary stuff in there. A half gallon bottle of bromine, about a quarter-pound lump of white phosphorus, some slabs of potassium and sodium, a canister of chlorine, etc. etc. Heh. Too bad the high school couldn't donate some of that stuff to me. ) She also gave me the kindest, most helpful reference letter when I applied to various colleges. I spoke with her via e-mail about a year ago and mentioned my element collection. She asked me to come down to the school one day to show off some of my pieces. So I brought out my cesium, osmium, indium, phosphorus, tungsten, and barium samples. It felt kind of good being up in front of a classroom and having everybody paying close attention to my every word. (This was an AP Chemistry class, so the kids in there actually wanted to be in there). She also downloaded my periodic table photograph and had it printed out on a giant poster sheet. That was pretty cool to see. I should probably drop her a line and see how things are going.

Not to mention against the forum rules. Back on topic. I've seen this before and it's basically a teflon/teflon derivative. If it was pure fluorine gas that they put on the fabric, it would have ignited. lol.

What's funny is that when you're young, people tend to snicker and laugh if you are into chemistry and know a lot about it. Yet when you get older, I've found that people become more impressed and whatnot. For you budullewraagh, the AP Chemistry test should be know problem. I was able to score a 5 on it without any problems at all. The SAT II in Chemistry is another good exam to take. It's graded like the SATs, but on a scale of 200-800. (You get 200 for putting your name on the paper). I took that test twice and got a 790 the first time, but took it again because I knew I could do better. On the second try I scored an 800. For some reason, I always do very well on standardized chemistry exams. I had to take the standardized ACS exams for my organic and physical chemistry courses, and if not for those exams I may not have passed. However, I did so well on them that my grades for the courses were boosted tremendously.

I think an easier to understand example of a single displacement reaction is putting copper metal in a solution of silver nitrate. Cu(s) + AgNO3(aq) --> CuNO3(aq) + Ag(s). The copper metal replaces the silver ions in solution forming silver metal and copper ions. The solution turns a blue-green color due to the presence of the copper ions. Another easy to see 'double replacement' reaction is the addition of silver nitrate to sodium chloride. The silver will immediately take the place of the sodium and give you silver chloride, while the sodium will remain in soultion at the sodium ion. However, you can filter the solution to get the AgCl out and evaporate the filtrate to dryness to get the sodium nitrate. NaCl(aq) + AgNO3(aq) --> NaNO3(aq) + AgCl(s) That one might be easier to actually 'see' the double replacment than the potassium chloride/sodium nitrate reaction.

Okay, but I just wanted to make sure you didn't get docked for little things. (I have always read and always seen many sources where flux was the name given to CaF2 since it was used to make the metal ore 'flow' better. Also, the word 'flux' is derived from the latin word 'fluere').

Yeah, my parents aren't too happy with all the elements I have, but I told them that once they get a degree in chemistry and known what the hell they're talking about, then I'll pay attention to them. Sadly, it's because of my degree in chemistry that I'm still at home at the age of 24. The cost of living around here has truly skyrocketed, but I'm saving up and hopefully by this time next year I'll have the down payment ready for my own place. But anway, I'm just happy to be getting that small bit of Uranium and have placed an order at United Nuclear for their 1' x 1' lead sheet to line a small wooden box I have. This weekend I'll sand the box and give it a nice staining and then a glossy polyurethane coating so that it will look really sharp. I may even gold plate the hinges and latching mechanism on it so it will really stand out.

Very nice. The only thing that came to my attention was where the origin of the name was defined. You are correct in that the origin of Fluorine's name is the Latin word 'fluere', but you're incorrect on what 'fluere' means. Fluere means 'To Flow', not 'To Flux'. (The word 'Flux' is also from the Latin word 'fluere' since a flux allows a metal ore to flow better by lowering its melting point).

Yes, it does ionize in water, but in the same way that table salt does. If you remove the water, the HCl comes right back.

Amygdalin is a compound that breaks down into HCN in the digestive tract of someone who eats it. It's a defense mechanism for the plant to prevent animals from digesting its seeds.

'Peroxide' also denotes that there is a bond in the molecule between the two oxygen atoms. So each oxygen has a bond to another oxygen atom and the chlorine atom.

Yes, that is true. Almonds have a compound in them which has a cyanide portion to it which is readily noticed when the almonds go bad. You could probably do a quick google search and find out the exact details. A lot of fruits have a cyanide producing compound in them called amygdalin(sp?). Peach pits, apple seeds, and a bunch of other 'innards' have it. I know that if you were to eat enough apple seeds or a few peach pits, you can get severely ill. There have been quite a few documented ER cases of small children eating too many apple seeds and displaying the classic cyanide poisoning symptoms.

lmao. Yeah, trying to do that would wind up getting you killed. Plus, the color would be completely off. I do know that heroin is frequently cut with compounds like cornstarch, or flour and quinine is added to it to keep the bitter taste. The idiots cut heroin with brown sugar and are generally shot as the sweet taste is a clear giveaway.

The one good thing about the halogens and other toxic gases like HCN and hydrogen sulfide is that the human nose is incredibly sensitive to them. You can smell cyanide gas, hydrogen sulfide gas, chlorine, bromine, and iodine long before they reach toxic concentrations. The only problem is that many of these toxic gases will 'anesthetize' your ability to smell so shortly thereafter you are unable to smell them. (This is somewhat gross, but it explains why after a short while you can't smell a nasty fart, but if someone else walks into the room they can quickly notice it. ) With chlorine, you easily smell the chlorine gas escaping from a bottle of bleach, but it is such a vanishingly small quantity that it poses no danger. Same thing from a swimming pool. In college I did an inventory of my school's chemical supplies and spent a few hours down by the cyanides and thiocyanites(sp?). I could easily smell the bitter almond odor coming from them and had a nasty headache for a few hours afterwards. In my toxicology class in college, my nose actually helped avert a major problem. We were doing analysis of arsenic poisoning samples, and had to do some procedure which generated arsine gas. We were told before hand to do all of this in the fume hood due to the toxicity of arsine. The professor also mentioned to us that it had a garlic-like odor. Well, halfway through the lab I noticed a VERY faint odor of garlic. I told the professor, but he didn't smell anything. However, he looked around the lab and saw one 20 mL vial which was out in the open by accident. It was indeed generating a little bit of arsine. So we quickly put it back in the fume hood and all was averted. So when working with chemicals, it's crucial to have a good sense of smell. This is why I always avoided doing anything potentially 'dangerous' when I had a stuffed up nose. Removing your sense of smell can lead to major trouble.