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The water molecules undergo a sort of attraction between them. This attraction is due to $\ce{H}$ atoms being attracted by the oxygen atoms of neighboring water molecules. At the surface of the water this attraction produces a sort of "skin" due to the attraction of the molecules between them. If a solid is touching this surface, it may produce a similar ...


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A test kit means a set of solutions for repeated use until the are spent. How many analysis can be done should be noted on the kit package. Paper strips are easier to use, but may not be better for result.


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The comments more or less say it all. Wearing gloves is a good idea with just about any chemical, not only to protect you but also to protect the chemical from contamination. For instance, if you find chloride in your sample you might want to be sure said chloride is not from salt on your skin.


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It works on the principle of hydrophobic interactions [...] That part of the statement is fairly accurate. While "normal phase" chromatography has a stationary phase that is capable of hydrogen bonding, the reverse phase stationary phase is not. Rather on focusing on the complexity of the process, I will compare reverse phase with ion exchange ...


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"It works on the principle of hydrophobic interactions hence the more nonpolar the material is, the longer it will be retained." ? It is a very crude, first order, approximation. A philosophical then arises, what is "non-polar" material and how would we measure it's nonpolarity? One should immediately start to see problems with the words like polarity...an ...


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I suspect this is very likely a sentence adapted from of one of the methods from the Russian State Pharmacopoeia (RSP), which has numerous entries for the adverb «потенциометрически» (Eng. “potentiometrically”). For instance, there is a nearly identical match in the normative section for the preparation of acetate buffer solution, ОФС.1.3.0003.15-1.27 ...


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For the given problem there isn't much $\ce{CO}$ created. Given that the question is multiple choice an exact amount isn't needed. The problem only needs to be solve close enough to determine which choice is the answer. So assume complete combustion and then guess that the answer will be about 5% high. If octane, $\ce{C8H18}$, is completely burned with ...


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This practice is done in analytical chemistry in order to minimize the relative weighing error on the balance. Preferring a larger formula weight for a primary standard has nothing to do with impurity levels. We have to start with the highest purity standard. For example, you wish to prepare a 0.010 M solution of oxalic acid dihydrate in 1 L flask. Its ...


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The reasons for the change in internuclear separation and the imporance of the Franck-Condon factors, as has been clearly pointed out in answers and comments. The FC factors determine the strengths of transitions from $M$ to $M^{+.}$ and to clarify this figure below shows a simple calculation based on harmonic oscillator wavefunctions of the effect of ...


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Well there is a pretty simple way, that you can do in any laboratory by standard reagents too. React the unknown mixture with $\ce{NH4OH + NH4Cl}$ (ammonium chloride is put as a standard to prevent the precipitation of Zn, Mn, Cu and Ni hydroxides, however, you don't have those in your sample, so you can proceed with only ammonium hydroxide too) now you will ...


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If you add NaF, it will make a complex with Fe(III) that will not react any more with any reagent later on. Cobalt may be recognized by adding solid NH4CNS and some amyl alcohol. If there is Cobalt in the solution, the alcohol phase will get blue. Iron must be previously eliminated by adding a little solid potassium or sodium fluoride. Fe(III) may be ...


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Why is it unusual (as it seems to be implicitly implied) that the bond lengths of the molecular ion in its ground state somehow end up being larger than the bond lengths of the molecular ion in its vibrationally excited state? It's not so much about whether the bond length in $\ce{M^.+}$ is larger or smaller than that in $\ce{M}$; it's more about whether ...


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