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Without standard solutions and a fluorimeter, you can do a side-by-side comparison using a commercial tonic water and your solution. I just prevailed in getting a poor photograph of the beautiful blue fluorescence from a commercial tonic water (begins with an S), using 405 nm excitation (BluRay laser diode). The photo is below: The two cuvettes contain ...


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There are no $\ce{NaCl}$ molecules in the solid salt nor in solution. In solid salt, there are $\ce{Na+}$ ions, surrounded by 6 $\ce{Cl-}$ ions, while each $\ce{Cl-}$ is similarly surrounded by 6 $\ce{Na+}$ ions. Here is the Wikipedia picture of the structure. During the dissolution, water molecules reach for a particular ion, oriented toward it by the ...


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Sodium carbonate indeed dissociates in water : $$\ce{Na2CO3 <=> 2 Na+ + CO3^2-}$$ But that is just beginning, as in solutions with carbonates, bicarbonates or dissolved carbon dioxide happen multiple chemical equilibriums: ( See a lot of info at Carbonic acid on Wikipedia): Carbonate anion partially hydrolyzes in water: $$\ce{CO3^2- + H+ <=> ...


3

Another possibility is the grease spot photometer (aka Bunsen photometer) German Wiki page. This can be homemade, you need a piece of paper, some wax or oil, two light sources, a meter stick and for the measurement of solutions also some e.g. cardboard to shield unwanted light. Also the darker the room, the better. The underlying idea is that light ...


2

Yes, there are numerous known lead(II) o-phenanthroline complexes with thiocyanate, perchlorate and bulkier organic ligands. As for nitrate, Bytheway et al. [1] reported synthesis (from lead(II) nitrate in methanol) and crystal structure of bis((1,10-phenanthroline)-(nitrato-O,O'))-lead(II): Figure 1. crystal structure of $\ce{[(phen)2Pb(NO3)2]}$ (CCDC: ...


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Making the solution in a single step is inaccurate up to impossible. Try to find a crystal of lead nitrate with the mass close enough to $\pu{1 mg}$ Try to weight up $\pu{1 mg}$ on scales with good enough accuracy. Try to make such $\pu{1 ppm}$ solution stable enough. The usual thing is to create a concentrated stock solution ( e.g $\pu{1000 ppm}$ and ...


1

I was thinking of a practical example where such an equation could be applied. It is not easy. A solid should react with a liquid, both being insoluble in water. And this reaction should produce two substances both soluble in water. I don't see many possibilities for this reaction. A may be a metal (maybe iron $\ce{Fe},$ or even gold $\ce{Au}),$ and $\ce{B}$ ...


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The amount of pure solid or liquid does not affect equilibrium, having chemical activity independent on amount, formally assigned to 1. If a solvent is in abundance wrt solutes, it is often considered still as approximately pure solvent, e.g water in context of diluted water solutions. The aqueous (aq) compounds definitely are not pure liquid. They are ...


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In the old book from Hopkin and Williams, Organic Reagents for Mineral Analysis. London (1933), the following information can be found in the Chapter "Diphenylthiocarbazone, or Dithizone". Diphenylthiocarbazone is a black powder, insoluble in water, but soluble in organic solvants, giving green solutions. Its main application is its reaction with lead. ...


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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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Yes, do use household dilute H2O2 but, in general, do not use commercial percarbonates powders as they can contain an additive to convert the friendly percarbonate into more powerful Peracetic acid (PAA). The latter allows the otherwise weak bleaching power of the H2O2 to compete with chlorine-based bleaching. However, this comes at a price (safety). Hence, ...


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The reaction system can be described as: $\ce{H2O <=> H+ + OH-}$ $\ce{H+ + CO3^{2-} <=> HCO3-}, \mathrm{p}K_\mathrm{a2}=10.33$ Note, the net of the first two reactions imply a rise in pH in the presence of carbonate. Further, with time and carbon dioxide exposure: $\ce{H2O + CO2 <=> HCO3- + H+}$ $\ce{H2CO3 <=> H2O + CO2}$ And, ...


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