All Questions
45,379
questions
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what really happens when an electron pair is shared in a bond?
I've never been able to understand how bonding between two atoms works.
When two atoms share an electron pair, does it mean the valence electrons of both atoms stop revolving in their shells and stop ...
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2
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How can adding a strong base to a weak base be the same as a strong base in solution problem?
In professor's lecture on acid-base titration, professor says (at this point of the video, link should start about the time she says it) adding a strong base to a weak base should be treated as a ...
- 848
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1
answer
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Do Electron-Withdrawing-Groups give an hypsochromic shift or a bathochromic one? and why?
I'm not familiar with this topic,but i know that bathochromic shifts occur when the energy gap between energy levels of the substituted molecule, are lower than the unsubstituted one;viceversa ...
CommunityBot
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Pump tubing for Sulfuric acid at 130c?
I'm looking for peristaltic pump tubing that is capable of withstanding sulfuric acid at 130 c.
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3
answers
684
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Disposal of Silver Halides dissolved in Ammonium Hydroxide
I was reading the Lab Manual for Chemistry prepared by the NCERT . While going through the the test for Chloride ions (pg 88) I came across the following Hazard Warning :
The solution obtained after
...
- 29.2k
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No. of Transition States
enter image description here
So in this question I had gotten the answer as 5 Transition states, however the official answer key states it to be 6.
Upon digging further for resources I found a ...
-1
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1
answer
64
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Why do we only use the principal quantum number to calculate the energy of an electron in an H atom?
According to my high school textbook the energy of an electron in a hydrogen atom is $E = -13.6/n^2~\pu{eV}$, where $n$ is the principal quantum number of the orbital in which the electron is present.
...
- 29.2k
1
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22
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Struggling to compute the effect of anthropogenic nitrous oxide on atmospheric ozone
I'm trying to compute the effect of anthropogenic nitrous oxide on atmospheric ozone; I have no background in chemistry and thus my calculations are rather simple. Moreover, they seem to be wrong.
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22
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Why pyridine-d5 solvent deshielded chemical shift in proton NMR?
Why pyridine-d5 solvent deshielded chemical shift in proton NMR?
The structure I sent for proton NMR dissolved in pyridine produce almost similar structure as the reference I found. However, this ...
2
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0
answers
22
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Is the surface electron affinity of (tribasic) sodium- or calcium phosphate higher?
Let's imagine, we have two polycrystalline samples: $\ce{Ca3(PO4)2}$ and $\ce{Na3PO4}$. A free electron is added to both. Some heat is released.
I wanted to check whether my reasoning about this ...
- 256
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Identifying the rate-determining step from an energy-reaction coordinate diagram
I was wondering how a rate-determining step would be identified for an energy-reaction coordinate diagram. The RDS would be the step with the highest activiation energy, but relative to what? Relative ...
- 415
5
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4
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3k
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Unexpected reaction during acid hydrolysis of cellulose
Recently I tried to hydrolyze some cellulose:
I added some acid to it ($\ce{H2SO4}$) then noticed nothing. Even after a few days there was no visible change and after doing some tests for glucose, ...
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0
answers
29
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Delocalization of Benzene's π-electrons through MO theory
I was just one point away from commenting on the answer in this (Hybrid orbitals forming molecular orbitals) else I would have commented - "So you mean you have two MO theories? The simplistic ...
6
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2
answers
286
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Substitute HS Experiment for Synthesis/Decomposition of HgO
In Elements of Chemistry by Antoine Lavoisier, he details a pair of experiments used to determine atmospheric composition:
First, he allowed mercury to simmer in a fixed volume of air over several ...
- 34.1k
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22
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How to derive absolute temperature scale from Carnot engine?
This question is about how to obtain an absolute or thermodynamic temperature scale using a Carnot engine.
The reasoning below appears in the book "Heat and Thermodynamics" by Zemansky and ...
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4
votes
1
answer
601
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Differentiating random and ordered sequential mechanisms in enzyme kinetics
Can random and ordered sequential mechanisms be descern by Lineweaver-Burk plot? Why or why not? Because for orederd sequential mechanism I got different LB plot depending on which substrate is held ...
- 994
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1
answer
54
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Precessional frequency in H-NMR
Suppose we have a hydrogen nucleus. Now, let's apply an external magnetic field $B$. As the magnetic field is applied, the hydrogen nucleus undergoes precessional motion about its own axis with ...
1
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2
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Why don't P graphs contradict Raoult's law graphs?
Our teacher gave us the following question:
1 mole each of liquids A, B are mixed in a piston-type vessel and piston is moved slowly and isothermally. (PA0 = 75 torr and PB0 = 25 Torr)
Find:
(a) ...
CommunityBot
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2
answers
57
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Identify the property to distinguish among different materials
Context: My son is studying in 6th grade, he had a question like this.
Vinegar, lemon juice, wheat flour, diesel and mustard oil can be distinguished on the basis of a property called
Hardness
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- 42.6k
5
votes
3
answers
3k
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Are coke (solid fuel from coal) and charcoal same thing obtained from different sources?
As coke is obtained from destructive distillation of coal, and charcoal from destructive distillation of substance other than coal (like wood and animal bones), are both the same thing, with charcoal ...
- 26.2k
3
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1
answer
160
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Formation of Goethite
Probably a simple question: When you're mixing potassium hydroxide ($\ce{KOH}$) with iron nitrate ($\ce{(FeNO3)3}$) to form ferrihydrate, does the temperature have to be below $\pu{60 ^\circ C}$?
- 26.2k
2
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1
answer
253
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What is the link between hydrogen production and potassium oxide?
Is there an industrial process that produces hydrogen with potassium oxide as a catalyst?
Or is there a process for the production of potassium oxide that has hydrogen as a by-product?
- 26.2k
2
votes
2
answers
1k
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Can Na2CO3 remove temporary hardness of water?
This was asked in my test and I remembered that all compounds that can remove permanent hardness of water can remove temporary hardness of water also. But my teacher marked it wrong and I cannot find ...
- 26.2k
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2
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How is mercury produced in industry? [closed]
Mercury is the only metal that exists in a liquid state at room temperature.
In which form is mercury extracted from its ore?
If it produced as a solid, how and when is it turned into a liquid?
- 26.2k
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votes
1
answer
40
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Electron configuration of ionized Copper
I am trying to think about the electron configuration of copper by adding electrons one by one, starting from a bare copper nucleus. My understanding is that the violation of the Aufbau principle ...
- 852
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votes
2
answers
1k
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What surface treatment can turn nickel black?
Questions:
The detailed surface treatment to turn nickel plated steel black.
The reaction mechanism of the process.
Methods:
(preferred) Anodizing, oxidizing : The only black nickel oxide is $\ce{...
- 256
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1
answer
44
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Phenol reaction with nitration mixture
When phenol is reacted with nitration mixture my teacher said that picric acid as minor product and a major oxidation product. Is that oxidation product benzoquinone or anything else?
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0
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27
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Does zinc form any sulfosalts that are not reactive to chromium?
If extremely fine chromium powder is made in a ball mill under inert gas atmosphere, is it possible that adding a sulfosalt of zinc to this process yields a mix of these powders without reaction with ...
- 256
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0
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56
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SLURM job script - why is the tmp local directory deleted before archiving can occur? How to prevent this?
I wrote a SLURM job script to run a computational chemistry calculation using the CREST program (part of the xtb software package). In the script, I create a temporary directory on the local storage ...
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Why do nutrition facts label differ for canned Garbanzo Beans (Chickpeas)? [closed]
Looking at canned Chickpeas Garbanzo Beans from several vendors, it seems some vendors use "prepared Garbanzo Beans" while others just used "Garbanzo Beans". Some also have ...
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