# Tag Info

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You might try a solution of cobalt(II) chloride, $\ce{CoCl2}$, in plain water (which might freeze) or in a mixture of water and ethanol or water and isopropyl alcohol. At some concentration, which you'd experimentally determine, it should turn from pink to blue on cooling to 273 K. See Flinn Scientific's site for more details. BTW, you might as well use ...

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DCPD - Dicalcium phosphate dihydrate DCPA - Dicalcium phosphate anhydrate Just summing up the comments I made, I came to following conclusions: Though DCPA is deliquescent and will soak water from air, it is not necessary that it will only form the dihydrate. Other hydrates may also form and with that, some additional compounds of mixed compositions will ...

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The temperature at which NOx is in equilibrium with its liquid and vapor phase at 1 atm is about –84 °C. Does that mean NOx exists as a liquid at that temperature? What about it's vapor phase then, because it's vapor and liquid phase should be at equilibrium, right? Yes, the vapor and liquid can coexist, provided P and T are on the coexistence (!) line (as ...

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It has already been suggested to use liquid nitrogen to cool oxygen and that is probably your best bet. You could research something called a cryocooler that can be used to condense air or pure oxygen but it is very costly and would not be worth it unless you plan on using a continuous supply liquid oxygen and/or nitrogen. If you're just going to do few ...

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You might want to raise the temperature a little bit as the reaction proceeds at 100-110°C to form formic acid. If the temperature is further raised to 260-280°C, then the reaction will proceed to form allyl alcohol. Formic acid has almost unlimited shelf life if unopened and is protected from heat and light sources. Allyl alcohol is stable in normal ...

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https://en.wikipedia.org/wiki/Copper%28II%29_chloride Aqueous solution prepared from copper(II) chloride contain a range of copper(II) complexes depending on concentration, temperature, and the presence of additional chloride ions. These species include blue color of $\ce{[Cu(H2O)6]^2+}$ and yellow or red color of the halide complexes of the formula \$\ce{[...

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Aluminum resists corrosion in neutral or slightly off-neutral water because of the very insoluble Al2O3 film on the metal. If you break this film, it will corrode the bare metal and reform. But if you scratch the Al and attach a cathode (a less active metal), you have a galvanic cell, and H2 can be evolved from this cathode as Al dissolves. The simplest ...

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Experimental design also comes into the fray. If you have an apparatus that is not quantitatively accurate, you can apply it to your experimental ssmple and to a control for ccx which you have a reference value of what you are trying to measure. You then calibrate your results to the known reference. I've used this approach at work, to compare acid ...

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To add to @Poutnik's and @M.Farooq's answers: Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means? No, because what you can and should do in terms of maths/statistics depends very much on your application and data generation/measurement processes. Using only mathematical means is ...

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Generally, improvement of measurement process has much better positive impact on results, than sophisticated mathematical processing of low quality data. But, sometimes we are forced to data what we have. There are 3 quantities: resolution = the smallest difference of directly measured value, distinguishable by the tool, precision = Level of uncertainty ...

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Your non-trivial question has a yes and a no. It is not possible to increase the accuracy of a dataset just by mathematical means. If you knew the systematic error in your data then you can do the arithmetic to correct the error. There is no a priori way to ascertain if your measurement tool lacks accuracy until and unless we have a reference for comparison. ...

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Eliminate the salt bridge. Test Al and Pb in a) Al(NO3)3 solution and b) (separately) Pb(NO3)2 solution. The salt bridge is for purity of thought and separation of the electrochemical reactions. A third possibility is to put an Al and a Pb electrode in HNO3 solution: any output voltage? Just try to get a cell going. Aluminum does not dissolve easily in HNO3,...

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1) Sodium dodecyl sulfate (SDS) is a solid anionic detergent. It can solubilize proteins and lipids that frame the cell membranes by degrading the cell (the proteins from the cell membrane get damaged and cell gets broken) and nuclear membranes that protect the DNA. This will help the cell membranes to separate and expose the chromosomes that contain the DNA....

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Such distillation is done every day in great quantities in closed ( air free) stills ; they are called refineries and chemical plants.

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It would be extremely dangerous to use a flammable solvent for a heat bath because any spill on the hot plate (or even worse, a Bunsen burner) could cause a fire. If you want to distill off ether, it is by far better to just use warm water from a tap or a kettle, and replace your hot bath regularly. Trust me, ether can spontaneously catch fire VERY easily !...

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