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Justonium

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Posts posted by Justonium

  1. For one thing, potassium sulfate is pretty soluble in water so your procedure would not work. As for the stability of copper chlorate, I believe it should be stable at room temperature, but I've never read anything about that compound in particular so I guess anything is possible. If you were to try to make it via a precipitation reaction, you would need to find out how soluble copper chlorate is, and then work from there to create a situation in which when a chlorate solution and a copper solution mix, the copper chlorate's solubility differs significantly from that of the other salt, so that it can be separated via filtration if it is less soluble, or purified by repeated crystalizations of the less soluble salt if it is more soluble. I suspect that it isn't very soluble in water, but again, only experimentation can tell for sure.

  2. I believe it's silver chloride. I have a little experience in photography, and I remember hearing silver chloride mentioned. Silver chloride slowly, very slowly, decomposes when exposed to light, ultraviolet in particular, into chlorine gas as well as silver metal that is seen as black/dark gray because its crystals are so small. I once made some rudimentary photosensitive paper myself, and all I did was coat ordinary printer paper with silver chloride. It worked brilliantly, although it did require a lengthy exposure time to pick up a good image.

     

    EDIT: Cripes, this thread is old!

  3. I'm not sure how to intergrate that; when I try 'u' substitution, representing the (x^2) as 'u', I can't get the 'du' in there:

    du = (d/dx)u = (d/dx)(x^2) = 2xdx

    There is no 'x' term in the expression, however, so that is where I get stuck.

  4. I made a little over gram of relatively pure sodium by lighting a mixture of powdered sodium hydroxide and powdered magnesium in a well cooled crucible with poor ventilation. I also ended up ruining the crucible with this method, as the extreme temperature changes that it was subjected to caused it to crack apart. Not a safe experiment to do at home, but I'm just pointing out that it's completely possible for sodium to be synthesized at home. I will not give the equation or the formula for this reaction, lest I encourage people who think they have enough experience to perform this. This is VERY DANGEROUS, and I was very far away from this crucible during the entire reaction. Being near it could result in splattering a very hot, very reactive molten mixture of sodium and sodium hydroxide onto your body, which will commence to burn and eat away at any skin that it touches. The only purpose of this post is to point out that it is possible to synthesize sodium at home.

  5. All of the responses in the main post seemed to me to be completely focused around the question: "How does this affect me?" This seemed to me to be looking for selfish excuses to do the right thing (not that that's a bad idea). But the way I see it, there's no greater importance of one person's happiness over any other person's, and so one of the motivators for me to help others is to remember that self is just an illusion, and that really, everything is all about just benefiting everybody's existences as much as possible, without regard to who it is, as long as the most people possible are benefited with the least possible harm done.

     

    To explain what I mean by saying that self is just an illusion, I'm going to create a little hypothetical scenario. Imagine that one day you switched consciousnesses with your friend. You're thoughts, memories, and personality; everything that is physically encoded into your body, stayed where it was, and your friend's likewise. The only thing that changed for you was that suddenly, you were you're friend. Neither you or you're friend would ever notice that anything at all peculiar had happened, and would go on continuing each others' lives as the other person. Is a scenario like this possible? What I'm trying to get at is that it doesn't matter. If you remove yourself from this incident, and look onto it as an outsider, would you say that this swap in consciousnesses has done the universe any worse or better? Both people still instill the exact same experiences into their consciousnesses, and while one may have swapped for the better and one for the worse, the exact same experiences still occur. As an outsider, one might be tempted to say that this swap is unnatural and wrong, and one would not normally volunteer to switch consciousnesses with another, but in this case, nobody was the wiser, so I see no wrong done, or even any relevance of considering whether there was a swap or not. My point is that each person's experiences get experienced. Who actually experiences them is quite irrelevant, because the entire sense of self is merely a creation of the mind.

  6. To help it dry faster, you can put it in a sealed bag along with some calcium chloride pellets (in another container) which can be bought from Home Depot for absorbing moisture from inside kitchen cabinets. This works best if you added close to equimolar proportions of ammonia and hydrochloric acid, but might be more difficult if you added too much ammonia. What i would do would be to add hydrochloric acid again after I passed the equivalence point, so that there is excess acid, and then dry it using solid sodium hydroxide as a dessicant. This stuff is horrible to get on you're skin though, so don't use if you aren't trained in handling it safely. I'm not sure how hydroscopic ammonium chloride is, but if it's not hydroscopic, then you might be able to just omit the dessication bag and just leave it out in the air. The thing that peeves me then, though, is that dust is landing in the solution while it dries, contaminating it. For highest purity, use excess acid and sodium hydroxide to dessicate it.

  7. Sodium metal is very useful for making sodium amide, which can then be used to make azides. Lead azide is one of the most practical primary explosives. Also, the reason people love throwing sodium metal into water so much is because it's fascinating that something will actually react with water, which is normally considered somewhat inert, so vigorously that it explodes. =) When I thew a bunch of sodium beads into water on my driveway, i got lots of cheers from my audience lol.

  8. It's the electrode. It's getting oxidized instead of the chloride ions in the solution. To oxidize these, you will need a non reactive electrode. Try graphite. Also, as you're cell runs, chlorine production will soon stop, as the solution becomes more basic. You will then be making hypochlorite ions instead. To prevent this, you need to separate the solutions by the anode and by the cathode. You can complete the circuit easily enough with a salt bridge--a sliced hotdog or a cloth soaked in electrolyte will work OK.

  9. I suppose I should have been more descriptive. The cathode would sit in cupric nitrate solution, and the silver would hang in sodium nitrate solution. The solutions would be connected by a salt bridge also containing sodium nitrate. As the cell runs, sodium ions in the anode solution should be replaced by silver ions, and the copper ions in the cathode solution should be replaced by sodium ions as they plate out. The reason I would use copper nitrate is that I don't want hydrogen to get reduced, lest a small amount of hydroxide ions find their way through the salt bridge and coat the silver anode with insoluble silver hydroxide. Any other people who think this process would work? It does not work with dissolving aluminum instead of silver, by the way; the aluminum just gets coated with oxide and the cell looses current.

  10. OK, instead of using hot nitric acid to dissolve old fine silver jewelry, would it work to just hang the cleaned jewelry in a solution of copper nitrate and use it as an anode? The copper would plate out on the cathode, and the silver would go into solution, right? What I'm worried about is that an oxide layer might coat the silver and stop the process. Is this method feasable, or do I need pure nitric acid? Mine's contaminated with hydrochloric that I'm too lazy to remove.

  11. The regenerator should be as small as possible to maximize efficiency, but you will have to compromise size with functionality. Personally, I never bothered to make one, I never needed efficiency in my Stirling engine; I was only making it rotate a CD and look nice on my shelf, not perform a task.

  12. The higher the temperature difference, the higher the efficiency, I'd say. The only limit to this trend is that you start losing a lot of efficiency if its so hot that the heat leaks out, but in a simple home made Stirling engine, you should not have to worry about that kind of limit. You just don't want to have so much heat that part of you're engine melts. I've made one before, and 2 cylinders of the same size works fine, the real deciding factor is the cycle you design for you're pistons. I use a sinusoidal cycle in which the hot side is one fourth of a period ahead of the cold side, just because of the simplicity of design using parts made from paperclips, but if you need to increase efficiency further, you can have both of you're piston rods connected to circular tracks in a disc which is spun by their pushes and pulls. You can design the track to have the optimal cycle for a 2 cylinder Stirling engine, which you can find online (I've seen videos on Youtube depicting it, calculated it using a computer program). This would be VERY difficult, however, and you don't get that much worse efficiency just using a regular sinusoidal cycle.

  13. yeah i will do that. thanks guys


    Merged post follows:

    Consecutive posts merged

    hey guys 1 more question how much baking soda to neutralize 100 ml of 15% HCL.

     

    thanks

     

    Calculate the molarity, (i believe its around 6M), and then you know that there will be 1/10th that many moles of HCL in 100mL (so about 0.6 moles). You need the same molarity of baking soda to neutralize it, so just multiply the moles by its molar mass (which is about 84g/mole), to get the grams of baking soda required. To make the solution safe to handle, add a little excess baking soda just in case, to get rid of any remaining acid.

  14. Try neutralizing it with a colorless base such as sodium sodium bicarbonate, sodium carbonate, or sodium hydroxide, and if the color remains, you know it is caused by impurities. If the color goes away, the test is inconclusive, though. Strange, I've never heard of hydrochloric acid having a color in high concentrations; I've used 12 molar before in small amounts, and I didn't notice any coloring, but maybe you can see it through a thicker cross section of the liquid, though I'd still be skeptical that hydrochloric acid would actually look green. I suspect that the green color is caused by contamination with ferrous ions. I don't see how pure hydrochloric acid could possibly look green, because neither hydronium ions nor chloride ions are green.

  15. the solubility of calcium hydroxide goes up immensely in hot water, so just boiling calcium hydroxide with sodium carbonate will give a good yield of lye even if there is not enough water to dissolve the original lime, because as the lime is consumed more can dissolve. The solubility does go down over time due to the increased number of hydroxide ions but it still remains somewhat high as long as the water is hot. The water must be distilled or de-ionized because tap water contains calcium, which will decrease the solubility of the lime.

  16. Oh, I'm just curious, that's all. Maybe if people had discovered this method that I'm looking for (if it exists), they could have started smelting aluminum before the required electrical technology was available. After all, metallic aluminum has been found in nature, so why should electricity be necessary to smelt it. It might be more economical, but I'm still curious.

     

    (By the way, most chemistry textbooks say that aluminum metal does not occur naturally, but they are just outdated, it is rarely found sparsely in volcanic rocks. I suspect very high pressures underground can force normally very product favored reactions backwards in order to reduce aluminum ions using LeChatelier's Principle.)

  17. Just use sodium hydroxide as a dessicant, it's easy to come by and works very well. Also, there's all this talk of which dessicant is better, all of them lower the vapor pressure of water to near zero, so the real solution to increasing dessication speed is to increase the surface area of the dessicant and optimally to increase air flow.

  18. I have done that same lab in my school, and we rinsed the filtered copper with acetone because copper reacts with air when it is wet to produce copper carbonate, which will make the sample turn green and weigh more. To prevent this reaction from happening while the copper was drying, we used acetone to rinse the water out. After the acetone drains off, the liquid which is wetting the copper is mostly acetone, which will not react. Acetone also evaporates faster than water, making the drying go faster, but this is not the main purpose of rinsing with acetone; water will still dry in a warm oven. If you're wondering why the copper would react, the copper reduced from the solution has a very porous surface, and reacts with air and water much more quickly than copper with a smooth surface (like a penny) would. I once left some freshly precipitated wet copper out in the air and it was already completely corroded less than an hour later.

  19. I recently watched this video on youtube

     

     

    cool stuff.

     

    I do have sulfuric and nitric acids, actually quite a bit of nitric stored in a chemical acid glass bottle, but I only have a little bit of sulfuric left, and I really don't feel like buying another bottle for $50 for my small-scale purposes described below, and its no fun to just buy nitrocellulose from a theater supply store. So this is what I was thinking:

     

    I do have a large amount of sodium bisulfate (yes bisulfate, not bisulfite). In water, I'm guessing that the sodium ions will completely fall off the HSO4- bisulfate ion. And although not all of the hydrogen ions will come off of the SO4-2, I think a good amount of them will when I dissolve the compound.

     

    So my question is if I made a saturated solution of sodium bisulfate, got it very cold, and mixed it with very cold conc. nitric acid, would it make a solution suitable for nitration?

     

    You'll need to dissolve the sodium bisulfate directly in ur concentrated nitric acid. The reaction won't work if your acids are dissociated.

  20. Does anybody know of a way that aluminum can be smelted without using electricity? Aluminum metal was never isolated until it was electrolyzed from molten ore, but now days, could there have been an alternate, if less practical, method of extraction discovered which requires no electricity or substances produced through electrolysis? Maybe some fancy way of cheating the reactivity series using coke to displace the aluminum?

  21. I used diameter when playing with the numbers because the steel balls size was given as a diameter. Using radius just changes the math a little, so I'll switch to radius for the moment. When you double the radius you more than double the area for storage. The area of a circle with a radius of .5 mm is .785398 sq mm. The area of a circle with a radius of 1 mm is 3.141593 sq mm. The area of a circle with a radius of 2 mm is 12.56637, and so on and so on. Add depth and you add mass. You can see that a disk with a radius of 2 mm is more than double the area of a disk with the a radius of 1 mm.

    So, I am somewhat confused when you say that whenever you doubled the radius the amount of energy you could store is also doubled. It seems more than doubled.

    I admit that using integrals to calculate is beyond my abilities for the moment, but the only way I can see you only doubling storage at double radius's is if you do use spokes, effectively removing mass from the disk, but why not take advantage of as much storage area as you can?

    Maybe I am not taking something into consideration here.

     

    What you need to understand is that surface area and energy stored per mass of disk are two different things. All I did was calculate the kinetic energies of two different sized discs, both spinning at different speeds so that the centrifugal force exerted on the outer layers would be equal in both discs. I then divided the total kinetic energy by the mass of each disc to find the energy stored per mass of material used. I think you were thinking total energy stored, in which case the bigger disc stores more energy, but what I was calculating was energy per mass, which also happened to increase. Also, the discs were not traveling at the same rpm. As a disc gets bigger, the maximium rpm possible decreases, while the maximum speed of the outer layer increases.

     

    Here is an example: a disc with a radius of 1m with its outer layer traveling at 1mps has the same centrifugal force acting upon its outer layer as a disc with a radius of 4m and an outer layer traveling at 2mps. The total kinetic energy of the second disc is 64 times that of the first disc, but once we take into account that the surface area of the second disc is 16 times that of the first, we know that the average energy density of the second disc is 4 times that of the first disc. Sorry I didn't show my math but you can calculate it if you want.

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