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One application of baking soda and vinegar is in cleaning a glass stovetop. You start with baking soda and water. The dissolved baking soda acts as a base, and the undissolved baking soda acts as mild abrasive. Once you are done cleaning, you need to get rid of the baking soda, and might want to adjust the pH of the cleaned surface. So at this point, you can ...


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You should not have a single sample preparation for all the elements. The sample preparation will depend on element by element. Your calculations have subtle misconceptions. Don't convert to concentrations but work with masses for such problems. So, you have 15 $\mu$g Mn in 15 g sample. This means you have 1 $\mu$g Mn in 1 g sample (see, I am avoiding ...


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So it finally turned out to be an artefact, sorry. The probe was protected by a small metallic tube. Somehow water condensed inside. Since this water is isolated from the main liquid, it performed its own phase-transition releasing its latent heat right next to the sensor. The effect was not appreciated when freezing the probe alone. I don't know why, maybe ...


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A nicely done experiment! Consider hand-warmers containing sodium acetate trihydrate, $\ce{NaCH3COO.3H2O}$. When heated above the melting point and then cooled, the compound does not quickly solidify, but can be greatly supercooled. Given an impetus to begin crystallization, such as the shock-wave produced by a "clicker" (or nucleation by a speck ...


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The best way to dissolve a black deposit on glass is to use a concentrated solution of $\ce{NaOH}$, about half water - half $\ce{NaOH}$. But take care ! This dissolution is highly exothermic. Try to prepare not more than a couple of milliliters of it in a test glass tube. The test tube will get hot during the mixing and dissolution operation. And take care ! ...


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