jdurg

I may recall having seen an image of liquid fluorine. If memory serves me right, it was a light yellow in color.

Just remember that H2S is an incredibly deadly gas which ranks up there with cyanide in terms of "ability to make you dead". SO2 is an incredibly corrosive gas that reacts somewhat exothermically with water (though not as intensely as SO3) to form sulfurous acid. You don't want to have either of those two boiling away on you as it would cause some pretty severe damage.

The law of conservation of matter only deals with the conservation of mass, not the number of moles. Look at the equation for the formation of ammonia via the Haber process. 3H2 + N2 => 2NH3. There you have 4 moles becoming two moles. The mass is the same but the number of moles is different. This is perfectly acceptable.

What you're essentially looking for is a polar solvent that will be liquid at temperatures between that of dry ice and liquid nitrogen. Hate to dissapoint you but I'm pretty sure you won't find one. The reason for this is that polar substances have pretty strong intermolecular attractions to each other which means that it's difficult to separate them. Therefore, they have higher melting and higher boiling points than similarly shaped, non-polar substances. In order to dissolve ice crystals, your solvent would need to be somewhat polar since water is a very polar substance. In addition, whatever it is must not react with the water. That's even more of a problem. In addition, if the substance needs to be able to dissolve simple organic molecules (which are typically not very polar at all) then it will have a harder time dissolving the ice crystals as well. There MAY be a substance that exists which is what you are looking for as I don't know the properties of every chemical on earth, but I can assure you that there is no common material which will suit your needs.

What keeps me going? The fact that I have no clue what happens when life ends and neither does anybody else. People may have their beliefs on what happens when you die, but nobody is certain of it. I'd hate to think one thing only to find out that I was completely wrong. What I believe may not be anywhere remotely close to what really happens and I'd hate to have wasted my life away as a result.

Here's a hint; 9.02 grams of Oxygen gas were consumed.

Not to mention the fact that quinine is horribly, horribly, HORRIBLY bitter and nobody in their right mind would knowingly ingest any large quantity of it. (though you may be fortuneate and be unable to taste quinine. If you can taste it, then once is all you'll ever need).

With gases, they mix kind of like two similar liquids mix. You can have two non-polar solvents of different densities, but if you mix them together they will form one mixture which will have the same density. Over a long period of time without any movement, then the two gases may separate but not to any really appreciable extent.

I'll have to look into that. I do want some of the metal to be oxidized and I'm not sure how well the lacquer would adhere to the spalling oxide. That's the reason for keeping it in the oil. I just think it would be really incredible looking to have half the ingot be a bright metallic surface while the other half has oxidized to the typical oxide color. (It'd be really neat to paint on there the name of the element so that when it all oxidizes again only the element name would be non-oxidized.)

Actually, the hot box is a nice little conversation piece. When I show people the uranium portion of my collection, it's always fun pulling out the stained and varnished box, then opening it up, removing the lead covering, then pulling out the vial with the uranium in there. What I will eventually plan on testing out with my lanthanum and neodymium samples is removing the oxidation from a part of it, then painting the metal with a clear lacquer that will adhere permanently to the metal's surface. This way a portion of it will be forever protected against oxidation but a part of it will also show the characteristic oxidation colors. The problem is finding a lacquer that will dry incredibly fast and also not dissolve away in the mineral oil that the metal is stored in. With the uranium, you are better off not removing the black oxide layer because the chance of spreading low level radioactive waste is pretty high if you are removing the "tarnish" from the metal's surface since the "tarnish" itself is mildly radioactive. After a while, the blackened surface takes on an odd iridescent coloring which is pretty neat to see. (This is really showing up on the turnings I have). Oh yeah, thanks for the compliment. It took quite a few years to put it together and more money than I'd care to think about, but it does feel good to see it complete. At this point it's just a matter of upgrading samples, preserving other samples, and increasing the amounts of certain samples. If I can give any advice about element collecting it would be to take advantage of every opportunity you get. If a sample suddenly becomes available to you, purchase it. If I didn't follow that advice I never would have gotten my white phosphorus, red phosphorus, cesium, rubidium, uranium, rhodium, arsenic, etc. for the prices that I did. If you ever have any questions, feel free to ask them here or if you'd like you can send me a PM if you don't want to post on the forums here.

It's a similar analogy to saying "I don't need to wear sunblock because I have a dark tan". Yeah if you have dark skin you won't burn as easily, but exposure to those ultraviolet rays still aren't a good thing. The same is true with gamma rays. Yeah they might not be super strong, but why increase your exposure when there is no need to? The amount of gamma rays given off is directly proportional to the surface area of your sample. If you have a small cube, then there won't be nearly as many gamma rays given off as a similarly massed thin sheet. (As the high density of the uranium does a damned good job at blocking radiation). Lead sheeting is not expensive at all and the extra protection it provides is a must. Short term exposure won't do much to you, but if this uranium is a part of your collection and it will be around you for a good long period of time then you must minimize the exposure.

Uranium gives off gamma rays in addition to the alpha particles, and a piece of paper isn't going to stop the gamma rays. I guarantee you that.

Hey no problem. When having an element collection the proper storage of your samples is FAR more important than anything else. As you said earlier, what good is a sample if it will corrode away to nothing in a short while? With Uranium the oxidation happens a bit slowly. I liken it to the oxidation of calcium metal. You can cut a piece off and it will show as a silvery metal, but after a little while you'll see it getting dull, then after a few hours it will be black. Even under oil it will blacken as time goes by. The piece I have was cut right in front of me, but in the amount of time it took for me to get back home (About an hour), the fresh silver surface of the Uranium had oxidized and become dark gray. It's now an iridescent black like the rest of the surface. For the glass, I use borosilicate glass in all of my element containers as it is a strong glass, doesn't really allow too much air through it, and it doesn't expand or contract a helluva lot as the temperature changes. If you fill a vial with oil, however, over time air will seep in and oxidize your sample. It doesn't really matter how well you seal it. You can only slow down the oxidation. So the oxidation of your Uranium is just something you'll have to accept. It's like the oxidation of Europium. Unless you can seal it in a glass ampoule in a dry box there will always be SOME oxidation on it. What I would do is take the vial and put the Uranium in there, then fill it to the top with the oil. Wrap the threads of the vial with some Teflon tape and be sure to wrap the Teflon around the threads moving clockwise. Now screw the cap on as tight as you can. Don't be afraid to use a good deal of force, but also don't use so much that you break the glass. With the cap tightly put in place, you can take some waterproof caulking and put a bead of sealant where the cap meets the vial. This will seal off the opening and prevent any air from getting in. While it will also make it so that you really can't open your container again, it will keep it sealed. Finally, wrap a layer of electrical tape around the top of the vial. The Uranium will react with any of the oxygen dissolved in the mineral oil, but if you poured it in there from a new bottle there shouldn't be a lot of dissolved O2, and if the vial was filled to the top with the oil there won't be a lot of airspace in the vial which would allow the O2 to dissolve. The biggest thing to remember is to keep some lead shielding around your uranium so that you aren't contanstly being exposed to the radiation. Depleted Uranium is moderately weak in terms of strength and DU that's at least one year old will have the same level of radioactivity for the next few thousand years. (As it takes quite a bit of time for the decay products to build up. During that first year, the Thorium and Protactinium are able to build up and add a tiny bit of radiation to your sample, but nothing earth shattering). All it takes is a few thin sheets of lead sheeting to block the radiation. So if you have a wooden box you can line it with a few layers of lead and everything will be fine. A good test to see if your shielding is effective is to take some unexposed polaroid film sheets and leave them, still sealed, around your Uranium container. After about a month of being next to your Uranium, develop the film. If your shielding is working you'll see nothing but a black photograph. If there is some "leaking" you'll see a hazy, fuzzy area where the gamma rays and generated x-rays were getting to the film. Collecting elements is a fun, but expensive and time consuming hobby. It's kind of sad when you finally get that last sample and have no more to collect. I have my collection hosted online at http://www.chemicalforums.com/~jdurg/FullPTP.zip, so feel free to take a look if you'd like. If you have any questions, please don't hesitate to contact me.

Uranium metal is VERY easily oxidized and is a royal pain in the arse to store because of that. It's a lot like the alkali metals in regards to how quickly and readily it will oxidize thanks to atmospheric oxygen/water. No matter what you do, it will darken and become covered with the black oxide layer. (I have run into the same problem with my metal chunk and turnings). For storage, your best bet is to get a tightly fitting borosilicate glass vial and completely submerge your uranium under mineral oil. If the entire vial is filled with oil there will be very little room for oxygen to get inside the vial. In addition, you'll need to ensure that the cap is sealed as tight as possible. Using a silicon caulking to permanently seal the vial shut may not be a bad idea. My uranium metal is stored in a small 20 mL glass vial whose threads are wrapped in Teflon tape and whose volume is completely filled with mineral oil. I then have it stored in a wooden box lined many times over with lead sheeting. Also, don't worry about scratching your uranium. Uranium metal is VERY solid. I.E. it doesn't scratch easily at all and is a very hard metal. Moving it over with steel tweezers isn't going to damage it at all.

Just to make sure we aren't going over your head with the topics here, you are aware of the different ways in which a radioactive atom decays, correct? There's alpha decay in which the atom spits off a helium nucleus and its mass drops by four and its atomic number drops by two. So U-238 (Z=92) spits off an alpha particle and becomes Th-234 (Z=90). Then we also have beta decay where a neutron inside the nucleus breaks apart into a proton and an electron where the electron gets thrown out of the nucleus. In this case, U-239 (Z=92) decays and becomes Np-239 (Z=93) while giving off an electron. There are a few other types of radioactive decay such as spontaneous fission, electron capture, etc. etc. but alpha and beta decay are the two more important ones. (There's also gamma ray emission, but that doesn't result in a new isotope or element being made). Inside nuclear reactors there are great number of nuclear reactions going on. In power plants, the majority of the reactions are the fission of certain isotopes. As you mentioned earlier, these fission events result in the creation of smaller atomic number nuclei. In addition, the fission results in the creation of neutrons. These neutrons do a few things; They either hit a nucleus causing it to split apart and spit out more neutrons, or they are absorbed by a nucleus causing a different reaction to occur, or they bounce around doing nothing. If the neutron is travelling at the right speed it will actually get absorbed by the nucleus of an atom causing that atom's atomic mass to increase by one. Generally speaking, this creates an unstable situation there. As a result, that atom will then decay. If it decays by beta emission, a neutron inside the nucleus will split apart forming a proton and an electron. The atomic number of the atom will go up by one while the mass stays the same. Because of this absorbed neutron, the atom has now increased its atomic number. This happens a LOT inside a nuclear reactor. U-238 will absorb a neutron and form U-239. U-239 isn't all that stable so it decays by spitting out a beta particle thus forming Np-239. Np-239 isn't all that stable either, so it decays and form Pu-239. Relatively speaking, plutonium-239 is somewhat stable so the concentration of plutonium builds up. Because of the absorbed neutrons, the uranium has turned into plutonium. Some isotopes are able to absorb even more neutrons and form higher atomic numbered elements such as Americium, Curium, Berkelium, etc. For the really heavy elements, they take the nuclei of various low mass elements and fling them at high speeds into a target made of a large atomic mass element. Every now and then the two nuclei will merge creating one of these 'superheavy' elements.

Carbon tetrachloride is a prime example. (CCl4)

The difference in mass between HCl and DCl is only 2.74% so in just about all reactions any type of difference will be negligible. In reactions involving water or any other compound where hydrogen is a larger % of the mass of the molecule then things can get more interesting. (As D2O is 11.1% heavier than H2O, and fully deuterated benzene is 7.7% heavier than normal benzene). Over a short time scale, the 2.74% difference between the rate of reaction of HCl and DCl will be negligible. You'd need a long, drawn out experiment to begin to see the differences and the overall kinetics of the experiment have to be slow enough so that the 2.74% difference in mass between the hydrogen isotopes can produce a slow enough step in the reaction for it to be seen.

Only the cost. DCl would cost a HELLUVA lot more than HCl would.

Wow. If I were a rat I'd be scared to death of aspartame! Oh wait, I'm not a rat. I'm a human being. (All kidding aside, I consume an ungodly amount of aspartame everyday in all of the diet soda I drink. As a diabetic for 23+ years now, if aspartame truly did cause cancer then we'd be seeing a MASSIVE increase in leukemias, lymphomas, and every other cancer that the article supposedly says is caused by aspartame. I have yet to hear of any increased cancer rates in insulin depedent diabetics who are most likely the biggest user base of aspartame).

If the minimum wage is increased, then companies that do not wish to pay the minimum wage will move their workforce overseas. Hell, right now companies that don't even pay any minimum wage positions are moving their workforces overseas where they don't have to pay anything remotely close to a fair wage. As a result, the number of jobs available here in the US will drop off and unemployment will go upwards. This will be just as much of a problem as the poverty level is right now. If minimum wage is moved upwards, then any goods and services which rely on minimum wage positions will move up in price also. Groceries will cost more, food will cost more, commerce will cost more. As this cost goes up, then the raises in minimum wage that were given will still not be enough to cover the rising cost of goods and services. It's a difficult thing to balance. Do you want 15% of your population below the poverty line and another 5% unemployed, or do you want 10% below the poverty line but another 10% unemployed?

Yup. Classic chemistry demo; letting HCl and NH3 gas interact to form NH4Cl crystals.

When I think about a computer I think about how I'm stuck at work and have many long hours ahead of me before I can go home.

What was contained in the test tube and what else was present in the fume hood? I can assure you that the crystals aren't ammonia because ammonia is a gas at STP and would not crystalize under any conditions one would find inside their home lab.

Organic acids are a PERFECT example of why you can't really say something is 100% ionic or something is 100% covalent. Numerous organic acids are VERY ionic in character while still being considered a covalent compound. A good analogy is to say that there are two types of temperatures; hot and cold. In reality, there are many subtle layers in between. In the example the original poster gave, the tests I described would easily tell the difference between the substances listed there.