# All Questions

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### How Does Internal Resistance of the Galvanic Cell Affect Voltage Drop of the Cell?

When galvanic cell operates or when current starts flowing in a circuit, voltage drops from electromotive force of the cell (EMF) because of internal resistance of the battery. There are three sources ...
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### How to estimate temperature loss of a mixture when we know the heat loss due to vaporisation of one of the component?

So I am modelling in Chemkin and want to include phase change phenomenon in my model. But there's no capability of phase change in Chemkin so I have to think of some out of the box method for this. So ...
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### Mix Liquid Paraffin and Distilled Water [closed]

I am trying to dilute Liquid Paraffin in water, I tried SLS but the foam is much. Please what should I do? Thank you and Best Wishes.
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### If a solvent can dissolve ionic compounds (water, ammonia) and metals are made of ions, then why can't said solvent dissolve a metal? [closed]

Here the solvent won't react with the metal(eg ammonia and sodium), and would the metal dissolve if there was no oxide layer?
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### Relation between common ion effect and the temperature of the solution [closed]

Adding extra Na+ in a saturated NaCl/water solution decreases the solubility of NaCl. How does this exactly happen? AFAIK, the solubility of a solid only decreases with the temperature of the solution....
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### In benzyne intermiediate of anisole why -I effect of OCH3 is considered not +M effect of it?

Here they considered -I effect of $\ce{OCH3}$ so carboanion is stable at orthroposition; But $\ce{OCH3}$ also shows $\text{+M}$ effect if $\text{+M}$ is shown carboanion will be stable at meta ...
31 views

### Action of Fuller's Earth on Marble and Limestone

Using Fuller's earth is a very common and harmless way to treat marble and limestone that has been damaged/corroded by atmostpheric pollutants such as PM2.5/PM10 carbon particles (Soot) , Oxides of ...
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### Cause of reversible reactions in terms of Gibbs free energy

Heading I recently learned about the standard Gibbs free energy change of reaction, ΔG=ΔH-TΔS, and how its sign indicates whether the conversion of (ALL) reactants and products is spontaneous or not. ...
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### How can I filtrate Pd2(dba)3 and P(o-tol)3? (Celite filtration failed)

I am conducting an organic synthesis involving Stille coupling, using $\ce{Pd2(dba)3}$ and $\ce{P(o-tol)3}$ as catalysts. Reaction solvent is toluene in which the catalysts also dissolve. Many texts ...
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### Calculating the apparent molecule length from density of the bulk [closed]

I'm interested to estimate the apparent length of the water molecule assuming it could be approximated as a cube. This is an intentional simplification. Calculating molecule length from volume in ...
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### Could freezing water or making jelly interpreted as a carnot cycle? [closed]

This was a question of a homework, but I'm really confused if it really makes sense. All that I read about carnot cycle always involves gases and even if those cases are reversible process how do we ...
456 views

### Can hydrogen peroxide reduce ferric ion to ferrous ion?

I have studied that hydrogen peroxide always oxidizes ferrous ion to ferric ion (source of study : NCERT Chemistry Part II, Textbook for Class XI), but a question came in IIT JEE 2015 which states: ...
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### Calculate the lattice energy of rubidium fluoride from the following data [closed]

Calculate the lattice energy of rubidium fluoride from the following data: Heat of sublimation of Rb(s)= +36kJ/mol ; Standard heat of formation of RbF(s)= +155kJ/mol ; Ionization energy of Rb(g) = +...
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### Finding shortest C=O bond length [closed]

I'm confused with this question. I get the feeling that in the presence of electron-donating groups, the bond length should increase, but I'm not sure why. Can someone help me out here? Thanks.
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### Is a hydrocarbon necessary for combustion? [closed]

Oxygen, heat and fuel are essential for combustion. What counts as a fuel? Is a hydrocarbon essential for combustion? Is combustion, say, of magnesium really combustion? And what's the difference ...
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### How do you precisely change the pH with calcium carbonate? [closed]

I produced some tamarind juice (made of boiled and filtered tamarind). Tamarind has a high content of tartaric acid. The $\mathrm{pH}$ is at $3.30$ which is too acidic for consumption. I want to raise ...
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### What is/was “uraneous oxide”? Was it an accepted name for a compound or mixed oxides of uranium?

In This National Technical Reports Library page for a 1965 report Method for Coating Actinide Particles in the list of keywords both Uranium compounds and Uraneous oxide are listed. But I don't find ...
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### How do you determine the Lewis formula using VSPER theory when one or more double or / and triple bonds occur? [closed]

I have some questions about determining the Lewis formulas of molecules. I basically proceed like this: if a molecule consists of two atoms, I draw it linearly, and select the bond so that if one ...
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### Confusion regarding nucleophilicity [duplicate]

My teacher told me that to compare nucleophilicity, check the size of the attacking atom. Bigger the attacking atom more the nucleophilicity. But while reading Solomon, I found out that the order of ...
328 views

### Looking for caffeine partition coefficients

As part of a project, I'm looking to carry out a liquid-liquid extraction of caffeine from an aqueous phase to an organic phase, using dichloromethane or ethyl acetate. So I'm looking for the ...
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### How to understand the chemical formula of Prussian blue complex w.r.t its crystal structure?

Note: Just to be clear, I do not refer to "complex molecules" (i.e. "complex" as "complicated"), but to actual complexes. I am trying to understand the structure of ...
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### Temperature control and side reactions in PPAA (T3P) couplings

In a lot of procedures for amide couplings (acid + amine) using PPAA, the coupling agent is added to a cooled solution of the acid, amine, and a non-nucleophilic base such as DIPEA. This is done even ...
Question: On complete reaction of $\ce{FeCl3}$ with oxalic acid in aqueous solution containing $\ce{KOH}$, resulted in the formation of product A. The secondary valency of $\ce{Fe}$ in the product A ...