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One thing worse then overtemperature is overtemperature at charging. One thing worse then overtemperature at charging is overtemperature at charging with charging >70-9x%. That speeds up the side reactions of eventual metallic lithium deposits with dialkylcarbonate at high charge. The reaction of either DMC or DEC with lithium was initiated at 180 K, a ...


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Yes, your voltage will change in accordance with the Nernst equation $$\Delta E_\text{cell} = - \frac{RT}{zF}\ln Q_{\text{rxn}}$$ So in your copper-zinc battery, where $$\ce{Cu^2+(aq) + Zn(s) -> Cu(s) + Zn^2+(aq)}$$ with a standard $E^\circ_\text{cell} \approx 1.10\text{V}$, setting the $\left[\ce{Cu^2+}\right] = 4\text{M}$ should raise your cell ...


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The aluminum oxide layer formed by anodizing will have substantially higher corrosion and abrasion resistance than non-anodized aluminum. For most applications, simple Type II sulfuric acid anodizing is sufficient. For maximum protection, Type III hard anodizing will yield a much thicker coating with substantially higher corrosion and abrasion resistance. ...


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I think this question is same as wondering as to why a certain cancer patient has a cancer in the kidney but not on the skin? Nobody knows. In the same way, rusting is a random process as well. It can start anywhere. This iron sheet is not ultrapure iron sheet of homogeneous nature. One can see a lot of spots in troughs and crests of this sheet. Secondly you ...


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The role of the HCl in copper plating and nickel plating solutions is to increase solution conductivity and increase anode corrosion and thus inhibit anode passivation which can deplete the bath of copper sulfate. Be careful with with adding too much HCl since it is a very difficult component of a bath to selectively remove, dummy plate or filter and high ...


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Let's restate the problem: we have two hydrogen half-cells with other stuff in them. Hydrogen electrodes will have voltages related to their pH, because that is the definition of a hydrogen electrode. Then it goes haywire: does one half-cell contain BaCl2 and the other contain Be(OH)2 at 0.5 M - certainly not BaCl and BeOH. In fact, Be(OH)2 is amphoteric and ...


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Salt Bridge is like a source which provides cations to the the half cell where the negative ions are more than the positive ones in the electrolyte . Similarly it gives anions to the half cell where positive ions are more than the negative ones in the electrolyte. It basically ensures continuity of the flow of electrons from anode to the cathode by ...


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Consider a salt bridge as a part of the cell electrolyte, that is not allowed to mix with the rest of electrolyte. For a particular ion, there are 2 cases: The ion is shared with the electrolyte part, from which the ion migrates toward the bridge. Then the ion gets depleted from electrolyte and not from the bridge. The ion is not shared with the ...


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The pH is a quantity that is measured in an aqueous solution by dipping a glass electrode in the solution. It is equal to -log[H+] in dilute solutions. For concentrations > 0.01 M, the pH deviates from log [H+], because the concentration [H+] should be calculated by dividing the number of moles H+ by the volume of the free water (and not the volume of the ...


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The volume of nickel plated is surface area times the thickness. That's $2m^2 \times \pu{0.03 cm} $. We'll use cubic cm as the units so it is: $2m \times 1m \times \pu{0.03 cm} = \pu{200 cm} \times \pu{100 cm} \times \pu{0.03 cm} = \pu{600 cm3} $ This helps to find the mass as the density is given as $\pu{8.9 g/cm3}$. The mass = density $\times$ volume = $...


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Actually, I think the question has an error in the EMF of the cell given. It should be $\pu{-0.413 V}$ rather than $\pu{0.413 V}.$ So, actually you are right in saying that the left half cell would be cathode if the EMF of the cell has to be positive. The mistake that you are doing is when you wrote the reduction potential of anode, you should have written ...


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This is not entirely true. Wikipedia lists several possible cathode materials and they are oxides. They may be "metallic" is the sense of being metallic conductors (some oxides are so), but they are ceramic compounds. The anode is typically Li-intercalated carbon (which is also a good conductor). Lithium intercalates readily into carbon, allowing a safer ...


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1) For what condition do the equations [6] and [7] apply? I think that [7] is for strong electrolytes at low concentration though im not sure. So what about at high concentrations of strong electrolytes? What about weak electrolytes? 2) When would you use equation [6], when would you use equation [7]? Are they equivalent? Equation [6] defines the molar ...


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