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22

Honey is indeed a complex mixture containing more than hundred compounds. As for Wikipedia and depending on the point of view it is a supersatured liquid solution a viscous supercooled liquid (in the sense that it can get so viscous as to appear solid, without affecting its status of being a supersatured solution, and undergoes glass transition). https://...

16

Melting and dissolving are all the same when you look at mixtures close to saturation. You can say water lowers the melting point of the sugar, or that the solubility of sugar increases with temperature. Different description, same fact. What makes this seem different from e.g. a salt water solution is that the molten (i.e. non-crystalline) sugar is fully ...

11

Yes, solubility of chlorine decreases drastically as the temperature rises, and it's almost insoluble in boiling water. That's also the reason why in the areas where tap water is chlorinated, it advised to boil it before drinking. Data from [1, p. 8]: Figure 5. Solubility of chlorine in water, hy­drochloric acid (two concentrations), and so­dium ...

10

Caesium salts are unapologetically ionic, and they typically have quite high mass solubilities in many solvents, including water. Assuming organic ions are allowed, caesium acetate ($\ce{H3CCO2^-Cs+}$) in particular has a remarkably high solubility of 9451 g/kg water at −2.5 °C, increasing to 13 455 g/L water at 88.5 °C. Caesium formate ($\ce{HCO2^-Cs+}$) ...

9

The following data is compiled from [1, pp. 4-44, 5-167]: Table 1. Selected solubility values of the inorganic compounds with significant ionic character at $25~\mathrm{^\circ C}$. $$\begin{array}{lc} \hline \text{Formula} & \text{Solubility in water}/\pu{g L-1}\\ \hline \ce{CsF} & 5730\\ \ce{SbF3} & 4920\\ \ce{LiClO3} & 4587\\ \ce{Pb(ClO4)... 8 There is not going to be a single definitive answer, primarily because of a wide gray zone surrounding the domain of ionic compounds. Besides, as Nikolau noted, the question is ambiguous. If you want mass concentration, then look at \ce{InI3} which claims a whopping 13100~\mathrm{g/L}. Pity that it is probably ionic in name only, judging by the ... 8 There is no "or" in the first place. An emulsion is a two-phased system, it is just that one phase comes in a form of small droplets. Small as they are, however, they are pretty big from molecular point of view. Now to the point. If you stir the liquids vigorously, you'll have an emulsion. Short of that, they will attempt to minimize the surface, and the ... 8 While calcium sulfate is usually termed insoluble, it is not the ‘sitting at the bottom like a rock’ type insoluble; rather, it is the ‘there’s no practical way for me to get the two ions into the same solution without precipitation, but I’m still able to identify both ions in solution’ type insoluble. Those sentences don’t really help, so let’s look at ... 7 Actually, the textbook should remove this question. You should discuss this with your teacher. It will be a service to future students. The heavier elements of group II elements form insoluble sulfates, phosphates and carbonates. Now carbonates display another interesting phenomenon. If you keep bubbling carbon dioxide in into a group II carbonate solution (... 6 The K_\mathrm{sp}(\ce{Co2S3}) value of magnitude of 10^{-124} appears in paper by Goates et al. [1]. The refined "thermodynamic" value of \pu{2.6e-124} that you've listed and is used by numerous textbook up to these days has been proposed in [2]. However, thirty years later (late 1980s) there's been another study by Licht [3], which showed significant ... 6 A saturated solution is at equilibrium (rate of dissolution is equal to rate of crystallization) with some equilibrium constant K_1. If you change the temperature of the system at equilibrium, you will observe a different equilibrium constant K_2. Whether the equilibrium constant increase or decreases is described by the Van't Hoff equation:$$\ln \left(\...

6

Oxygen is relatively insoluble in water, its solubility being only 264 $\mu M$ at $25^oC$. That explains in part why you (and fish) require dedicated oxygen carriers in your blood to transfer sufficient oxygen around your body. That oxygen is weakly soluble can be explained, as you point out, on the basis of the hydrophobic effect, which amounts to saying ...

6

Cyanide is generally better than iodide in transition metal complexes because it acts as a pi-acceptor. It has empty orbitals that overlap with the partially filled d-orbitals of the metal, lowering the energy of these electrons. Iodide is a sigma-donor, meaning that it donates electron density to empty metallic orbitals. The effect is small compared to a ...

6

In my version of the book the original assumption (step 7a) is shown to lead to a contradiction when later checked (logically, this form of proof is called reductio ad absurdum or proof by contradiction). The point is that you should 1) learn not to be afraid to apply assumptions, but that you should then 2) verify that the original assumption was indeed ...

5

You can also use the Henderson-Hasselbalch equation: $$\mathrm{pH} = \mathrm{p}K_{\mathrm{a}} + \log \frac{\ce{[A-]}}{\ce{[HA]}}$$ rearranges to: $$\mathrm{pH} - \mathrm{p}K_{\mathrm{a}} = \log \frac{\ce{[A-]}}{\ce{[HA]}}$$ $\log \frac{\ce{[A-]}}{\ce{[HA]}} > 0$ for conjugate base dominating. $\log \frac{\ce{[A-]}}{\ce{[HA]}} < 0$ for acid ...

5

Casein is a mixture of phosphoproteins found in milk that accounts for approximately 80% of the total protein content of cow milk (cow milk contains 3.3% total protein). Hence, it is easy to prepare casein as a pure protein from cow milk. Casein exists in milk as the water soluble calcium salt of a phosphoprotein (UC, Davis). Thus, it is usually prepared ...

5

Consider a $\pu{10.0 mL}$ solution containing $\pu{1.0e-10 M}$ each of $\ce{Ba(CN)2}$ and $\ce{BaI2}$. If $\pu{3.5e-9 mol}$ of $\ce{AgNO3(s)}$ is added to this solution, will any precipitate(s) form? If yes, what compound(s) will precipitate? $K_\mathrm{sp}(\ce{AgCN}) = \pu{6.0e-17}$; $K_\mathrm{sp}(\ce{AgI}) = \pu{8.5e-17}$. Assuming that $\ce{Ba(CN)2}... 5 As noted by Wikipedia, "Henry's Law is a gas law that states that the amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid." So you are absolutely right. 4 times the pressure of oxygen should result in 4 times as much oxygen being dissolved. The answer key for the problem must be wrong. User Delta_G made an ... 5 Well, acetone is at the same time polar (so it likes water) and lipophilic (so it likes fat). As such, it is a very good solvent. 4 The solubility of quinine sulfate in ethanol is temperature dependent. This reference 1 describes it as slightly soluble in EtOH at 25C, soluble at 80C. What you describe sounds like the material crystallised out of solution when you let it stand. Note: Ethanol is generally regarded as a polar solvent, and while the freebase of quinine is non-polar, any ... 4 I cannot guarantee the materials in this answer will meet all your requirements, so it would still be very helpful if anyone else could pitch in (especially an inorganic chemist or someone with hands-on knowledge of refractory materials). I will describe my thought process, which may ultimately be more useful than the suggestions themselves. Immediately, ... 4 The leftmost and rightmost parts of the galvanic cell notation are supposed to be electrodes, not electrolytes (no KBr (aq) and the likes of it there). What is more, the double vertical line represents the interface where the junction potential has been eliminated ((c) Atkins), i.e. salt bridge, which in this case is the interface between electrolytes. The ... 4 Yes, absolutely, all nitrate counts in solubility product regardless of source. The system cannot distinguish what a nitrate ion (or any dissociated species) was bonded to before it dissociated. 4 As propylene glycol can dissolve plastic... This claim is absurd. Propylene glycol cannot dissolve poly(olefin) polymers especially polypropylene or polyethylene. It is possible for glycols to cause paneling of containers made to such, but not dissolve; and certainly wouldn't happen in the amount of time it takes to perform an injection. 4 Water contains negligible amount of$\ce{CaCO3}$or$\ce{MgCO3}$, as these are almost insoluble in water. What you are interested in are bicarbonates$\ce{Ca(HCO3)2 + Mg(HCO3)2}$. Their content is known as the temporary or carbonate water hardness that can be expressed as$\ce{CaCO3}$equivalent. The complement to the carbonate hardness is the permanent ... 4 The solubility has been given solely to justify the application of the given method of gravimetric analysis. Since the majority of potassium salts are well or moderately soluble in water, for this analysis it's assumed that entire potassium content is brought to the solution. Since the solubility value of potassium tetraphenylborate is over a million times ... 4 The precipitation of lead phosphate would be due to the following reaction. $$\ce{3Pb^{2+} + 2PO4^{3-} <=> Pb3(PO4)2}$$ In acidic solution the phosphate ions would be protonated, thus reducing the concentration of$\ce{PO4^{3-}}$and increasing the solubility of$\ce{Pb^{2+}}$. But the precipitation of the phosphate is not lead's only reaction in ... 4 I believe have found a answer. It's valid mathematically, make sense physically but I don't know if chemically is true. I posted to community appreciation. There we go! The reactions ionization of weak acid: $$\ce{HA + H2O <=> H3O+ + A-}\qquad K_\ce{a}=\frac{\ce{[H3O+][A-]}}{\ce{[HA]}} \tag{1} \label{eq:KWeakAcid}$$ ionization of weak base:$$\... 3 Hydrogen iodide is not listed as miscible with water because it is a gas. Miscibility is a property generally ascribed to pairs of liquids. Hydrogen fluoride is a liquid, and so it can be described as miscible with water. HF is a weak acid, but its high solubility can be explained by the high polarity of the H-F bond and the ability of HF to be both a ... 3 As others noted, the effect of temperature is governed completely by$\Delta H$of dissolution. The reason that dissolution can have either positive or negative$\Delta H$is because the favorability is determined by the Gibbs free energy$\Delta G = \Delta H - T \Delta S$. If the$\Delta S$term is negative (before multiplication by -T) and$\Delta H\$ is ...

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