Unanswered Questions
948 questions with no upvoted or accepted answers
10
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Why are IUPAC's definitions of exo- and endothermic disconnected from the direction of heat flow?
I'm wondering if anyone can provide a rationale for IUPAC's definitions of exothermic and endothermic since they disconnect these terms from the direction of heat flow.
Specifically, here are IUPAC's ...
CommunityBot
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8
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0
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392
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What exactly is an "electron-sponge"?
What exactly an "electron-sponge" [behavior/action/property/system] nickname is, and what makes a material an "electron-sponge" (preferably, quantitatively)?
From what I found, it's typically a ...
- 38.4k
8
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Removal of nickel plating on MgB2 without damaging the boride?
I need to remove a nickel plating of a MgB2 wire without causing damage to the MgB2. I felt that electrolysis is the best method but I do not know what electrolyte to use for this. I also need to coat ...
CommunityBot
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7
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Why does entropy increase in reactions that make more molecules?
I used to understand this (more molecules ⇒ more degrees of freedom), but do no longer, because the total number of atoms is conserved, so translational d.o.f. should just be turned into internal d.o....
7
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Does phosphoric acid remove stainless steel electropolished layer?
Electropolished stainless steel has a high corrosion resistance due to the oxide film that is created during electropolishing. The film mainly consist of chromium(III) oxide.
Phosphoric acid is ...
- 815
6
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Do "pseudo Van der Waals" gases exist?
In college, when deriving the Langmuir isotherm for gas-solid adsorption, the professor proposed a modified version of the Van der Waals state equation, what he called the "pseudo Van der Waals ...
- 4,827
6
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Correct Definition of Absolute Electrode Potential
I thought absolute electrode potential is Galvani potential difference at the interface. However, it is given by following equation in John Bockris - Modern Electrochemistry (Ref.1): $$ E^M \mathrm{(...
- 865
6
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Why is the reverse aldol cleavage of fructose 1,6-bisphosphate highly endergonic under standard conditions?
I have another question similar to this one. I just don't have intuition for why reactions are thermodynamically favorable or unfavorable and I'd like to build it. This time I'd like to ask about ...
CommunityBot
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6
votes
1
answer
196
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Understanding elementary rate laws from a probability stand point
I am learning about chemical kinetics and dynamics and as I understand for a general chemical reaction
$$\ce{aA + bB -> cC + dD} $$ whose reaction rate, r, can be described by an elementary rate ...
CommunityBot
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6
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0
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Thermophysical properties of liquid Galden LS 230 between 25 °C and 230 °C
I'm looking for thermophysical properties of Galden LS 230, a liquid polymer (PFPE) produced by Solvay (https://www.solvay.com/en/markets-and-products/featured-products/Galden.html) at temperatures ...
CommunityBot
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6
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I found transition states (TS), but calculations aren't supported by experiment. Do I look for more TSs or somewhere else?
I'm using Gaussian to investigate a catalyst system.
Experimental evidence showed that one of three analogues (R = phenyl, Ph), yielded a benzosultam
when treated with 2,4,6-...
- 44.1k
6
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143
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Seeking titanium compound, melting point <1600 °C, decomposes to TiO
The title says it all. I’m new to glass making, and I need a titanium compound that will render me $\ce{TiO}$ through decomposition, and has a melting point under 1600 °C. Hopefully I can get one ...
CommunityBot
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6
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0
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89
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How can I compute the temperature change from the de-excitation of excited particle species?
The motivation for the question in the title is that I have some formula given,
$$\Delta T=\frac{3410\ \gamma_{O_2}}{2.5+\gamma_{O_2}},$$
where $\gamma_{O_2}$ is the molar fraction of oxygen in a ...
- 1,012
5
votes
1
answer
77
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How to remove glass shards out of a tiny hole to fit capillary tube?
This is oddly specific, but I am having trouble making the setup work for my electrochemical cell. We're doing Scanning Electrochemical Cell Microscopy (SECCM)* and the device has a capillary tube fit ...
5
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Dependence of elasticity on temperature and degree of vulcanization of typical commercial rubber band
I am doing a school experiment that tries to find how the elasticity of rubber band depends on temperature.
From all the research I have done, theory suggests stress to increase linearly with ...
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