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Question: What is the practical significance of the shape of conical flask (in US: Erlenmeyer flask)? An Erlenmeyer flask (also known as a conical flask or a titration flask) is a type of laboratory flask, which consists of a flat bottom, a conical body, and a cylindrical neck. The flask is created by the German chemist, Richard August Carl Emil Erlenmeyer (...


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If the sulfuric acid has $\pu{460 g } \ce{H2SO4}\pu{/L}$ then the molarity of sulfuric acid is: $\dfrac{\pu{460 g/L}}{\pu{98 g/mole}}= \pu{4.69 molar}$ As Alex pointed out for dilution to 3 M Sulphuric $C_1\cdot V_1 = C_2\cdot V_2$ $4.69\cdot V_1 = \pu{3 molar}\cdot \pu{1.00 L}$ $ V_1 = \dfrac{3}{4.69}\pu{ L} = \pu{0.640 L}$ So take $\pu{640 ml}$ of ...


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I'm not 100% sure if this will apply but you can probably use the formula C1V1 = C2V2. V1 being the volume of stock solution needed to make the new solution, C1 The concentration of stock solution, V2 The final volume of new solution, C2 The final concentration of new solution For example 5 mL of a 0.25 M solution from a 1 M solution, using the formula ...


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The calcium amount may change from one fruit to the next one, or from one day to another one, or from one field to another one. 20 % is not a significant difference between such a measurement and another one. And this may happen for any constituant, not specially for calcium.


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I have solubility s given in g/mL. I understand this as mass of solute m divided by volume of solvent V. Your confusion is arising from mixing the concept of solubility and concentration. Unfortunately, both are expressed the same way. You have to see the context. Most authors (like good scientists) try to write their experiment explicitly so that others ...


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Water and acetone form a polar/non-polar mix and due to strong bonds, the mix is less volatile than would be predicted by the Ideal Version of Rault's Law (which is a linear parametric weighing of the respective partial vapor pressures). This results in what is referred to as a negative deviation (as the curve is beneath the straight line associated with ...


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I'm not sure of any conventional ways of electroplating selenium, but you could use a technique such as magnetron sputtering to spray a thin film of selenium onto another metal. Heck, you could even use glass or wood if you wanted to do it that way. And if you're going for thin, this technique can get you some of the thinnest, smoothest layers of metal out ...


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From a purely standard chemistry perspective, the longer one allows a potentially slow reaction (attack of the outer membranes, for example) to occur, I would expect better results. Photochemistry is also an option to consider, which may be catalytic with other treatments. In particular, explore safe natural light sun bulbs (I would select the higher output,...


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Limiting reagent is the reactant used which produces lesser amount of the product as compared to other reactants if other reactants are used in sufficient amounts. Thus it limits the quantity of the product. Now, according to your question, Moles of CH4 = (Mass of CH4 taken)÷(Molecular mass of CH4) = 8/[12+(4×1)] = 8/16 = 0.5 moles of CH4 are ...


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1) Let us calculate first the $\ce{NH_4F}$ problem. The ion $\ce{F^-}$ reacts partially with water according to $$\ce{F^- + H_2O <=> HF + OH^-}$$ The equilibrium constant $K_b$ of this equilibrium is defined by $$K_b = \frac{[HF][OH^-]}{[F^-]}$$ The numerical value of $K_b$ is needed, but it is not tabulated. However it can be obtained from the ...


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User EdV comments above get to the heart of the matter. To summarize: Your first equation is typically how a chemist would write the reaction. $$\ce{3Pb(NO3)2 (aq) + 2(NH4)3PO4(aq) -> Pb3(PO4)2(s) + 6NH4NO3(aq)}$$ The equation is a "shorthand" explanation. What a chemist reads is: On the left hand side is that that two solutions are mixed together. ...


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WRONG SOLUTION: OP clarified that there are two separate solutions, not a mixture of the salts. Assuming: (1) that concentrations can be used instead of activities (bad assumption...) (2) The concentration of the ions $\ce{H2F-}$ and $\ce{F-}$ is so large that the final concentrations will be the same as the initial concentrations. (3) Since HF is a ...


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I've found a answer for my question from this question. The way to compute the conductivity of electrolyte with multiple ion types is given from the work Pawlowicz, Rich, ( 2008), Calculating the conductivity of natural waters, Limnol. Oceanogr. Methods, 6, doi:10.4319/lom.2008.6.489. For general case consider the system, which consist of $N_+$ number of ...


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First I would say that your measurement is not reliable enough. You say that you obtain 3 mg AgCl. 3 mg AgCl is nearly nothing. If you are not able to be more precise, it means that your amount of AgCl is between 2.5 mg and 3.5 mg. The uncertainty is about ± 17%. That is a huge uncertainty. Anyway your 3 mg AgCl contains 0.074 mg Cl which were in the 50 mL ...


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Energy is needed for separating positive from negative ions in the dissolution process. This energy is taken in the surrounding water. Water is loosing energy in the dissolution process. That is why the temperature of the water decreases. There is nothing special in using $NH_4Cl$. The same phenomena happens when dissolving a salt like $NaCl$ or any other ...


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An exothermic reaction occurs when the temperature of a system increases due to the evolution of heat. This heat is released into the surroundings, resulting in an overall negative quantity for the heat of reaction (-ΔE ). An endothermic reaction occurs when the temperature of an isolated system decreases while the surroundings of a non-isolated system ...


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