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If you mix CaCO3 + S and heat the mix, the first thing to occur will be that sulfur melts. Second, CaCO3 loses CO2 and becomes CaO. Third, sulfur boils off (or has already boiled off). A thought that perhaps CaS + O2 would form can be eliminated on the basis that roasting metal sulfides in air produces SO2 + the metal oxide. So the metal sulfide is unlikely....


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The part of the windshield that you are talking about is called the frit. This is typically made up of some form of high-heat enamel, and as far as I was able to find, it is intended to increase the surface roughness of the inside of the glass to increase the ability for the adhesive to stick to it. I was not able to find any specific mention for what type ...


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You need to know which acids are present in the sample, or determine the required amount experimentally. Without any knowledge of the pKa values of the acid or acids present, there could be very different scenarios. A pH of about 5 could be due to a high concentration of a weaker acid or a low concentration of a stronger acid. For example, 0.01 mM of HCl ...


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In nature fat is stored as triglycerides (TGs): Three fatty acid (FA) chains bound together by a glycerol backbone. Olive oil is mainly composed of TGs, though it also contains small amounts of free fatty acids (FFAs). An example of Triglyceride (from Wikipedia) Soap is commonly made via the reaction of triglycerides with a strong base: usually Sodium ...


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If you use tap-water together with Sodiumcarbonate, chances are that the residue is Calciumcarbonate (unless your tap-water is very soft). Calciumcarbonate is significantly less soluble in water, but can be dissolved in acid. I would try to put a bottle/arm in a hot 5% solution of acid (acetic acid is fine, personally I would prefer citric acid) to see if ...


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GermX thins when it hits your hands because of the sodium ions present in your hands. The polymer used in GermX is a polyelectrolyte - in this case it is poly(acyrlic acid) that has been neutralized with a base made with a large cation. The large cation is too large to effectively separate and quench the electrical repulsion between the neighboring negative ...


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As for safety, calcium chloride, $\ce{CaCl2}$, is in sea water and added to foods, such as beans and pickles. It's about as dangerous as table salt, sodium chloride, $\ce{NaCl}$ (actually, $\ce{CaCl2}$ is safer for concrete). However, it absorbs only so much water until it dissolves and stops being effective. What would you do with the puddle of $\ce{CaCl2}$...


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A compound, a mixture may explode under different conditions. As an example, for some of them it is heat, other require electric discharge or mecanical impact to decompose. There are classes of compounds with known examples of explosives (azides, picrates, fulminates) so one may infer new compounds within these classes equally might be explosives, too. ...


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$\ce{CaCO3}$ is easily decarboxylated to $\ce{CaO}$ in the heat of the fire. By dumping the ash into water you get a solution of $\ce{Ca(OH)2}$ and $\ce{K2CO3}$, and since $\ce{CaCO3}$ is less soluble than $\ce{Ca(OH)2}$ and $\ce{K2CO3}$ you end up with $\ce{KOH + Ca(OH)2}$ solution in one step and $\ce{CO2}$ dissolving into this solution will deplete ...


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