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I finally found the answer to the question I have made a huge mistake in the testing equation In order for a titration to happen the Formation constant $\ce{K}$ should be greater than or equal to $\ce{10^7}$ What I have written in my note book is $\ce{K''_{MY^{n-4}}} = \ce{K_{MY^{n-4}}α_{M^{n+}}α_{Y^{4-}}-α_{Y^{'}}}$ Which is incorrect it, Should be like ...


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You misinterpret the principle. It does not say if you add more salt, more salt dissolves. More generally, the principle focuses on changes of intensive properties, that do not change with the system scaling. The principle says if the thermodynamic activity of the solid had increased by adding more salt, more salt would have dissolved to decrease this ...


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You have several queries. First of let us look at the gradient method used by the authors. The HPLC gradient for synthetic colorants was 0 min A 100 p. cent, 10 min A 0 p. cent, 14 min A 100 p. cent. The HPLC gradient for natural carmine was 0 min A 80 p. cent, 20 min A 50 p. cent, 23 min A 30 p. cent, 25 min A 30 p. cent Factually, notice the trend in the ...


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OP's question: From the papers I've read, most if not all of them use the intercept with the $\mathrm{pH}$ axis instead of the $\log \left(\frac{\ce{In-}}{\ce{HIn}}\right)$ axis in this situation, why is this? Answer for this question is easy. According to the graphs plotted using the equation $\log \left(\frac{\ce{In-}}{\ce{HIn}}\right) = \mathrm{pH} - \...


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From the Toxic Substance Portal of ATSDR, "The [almond] odor of hydrogen cyanide is detectable at 2-10 ppm (OSHA PEL = 10 ppm), but does not provide adequate warning of hazardous concentrations. Perception of the odor is a genetic trait (20% to 40% of the general population cannot detect hydrogen cyanide)." However, from that same source, the NIOSH ...


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I contacted GoodFellow directly and they gave me the following answer: 93.9% AN: 93.9% AcryloNitrile 5.8% MA: 5.8% Methyl Acrylate 0.3% MS: 0.3% Methyl Sulfonate I guess different manufacturers may name their products as they see fit. In particular, for polymers that can share the same abbreviations, only the context and a good background knowledge of ...


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Gluten describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour. Given the requirement for an easily implemented chemical ...


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Since OP has productive conversation with Nicolas, I think the information extracted from chain of comments is good enough to convince OP has made fair enough effort to solve this homework. The following steps might be helpful as well: OP didn't indicate what $\ce{Zn/EDTA}$ molar ratio would this reaction take. As rule of thumb, it is generally $1:1$. Thus, $...


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ELSD is an acronym for Evaporative Light Scattering Detector. It is used as a quasi-universal detector for HPLC. The first step is the nebulization of the column effluents with a dry gas as you have mentioned. If the column effluents contain any non-volatile analyte, then those will form minute particles. The mintue particles become suspended in the gas ...


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I'll try to give some information that would help you according to your statement in the question: I've actually been trying to find more generalised information to help with the assignment of a different (but similar) cyclohexene compound. First of all, you may have found now from the two answers given elsewhere that there are no way you can assign all ...


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I think there is no perfect answer to this situation. In general when the flow is stopped to any detector in an HPLC experiment, there is a change in baseline, and when the flow is re-started, ghost peaks appear in chromatogram. I am talking about optical detectors such as UV, fluorescence, refractive index etc. Same thing happens in MS and perhaps LC ESI-MS ...


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Referring to your comment on Buttonwood's answer: Unfortunately, in this case I only have 1D HNMR and IR available to analyse the product If this is really the case, then you are essentially out of luck. It is not possible to extract much information from a series of overlapping multiplets, which may well be coupled to each other (these strong coupling ...


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In short: Recording NMR is not limited to $\mathrm{^1H}$, but for isotopes of other nuclei, too if their magnetic spin is not zero. $\mathrm{^{13}C}$, for example is an other routinely recorded sample. Literally, you don't have to stick to 1D, but may record correlation spectra, (not exhaustive list:) either between nuclei of same type (e.g., $\{\mathrm{^...


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I sort of feel this is actually more of a mathematical/statistical/modeling related question than traditional chemistry. In essence, one argument is that the sample derived effective API concentration is impacted by possible changes in the particle size distribution due to grinding. Now, there are, in effect, known statistical distributions that address ...


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First, for reasons I'll point out later this is a poorly made-up problem which was only designed to test significant figures, not to teach anything real about chemistry. Second there are no special rules for "word problems" using significant figures. The gist is that significant figures are a simple method to do error propagation in calculations. ...


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