May 25, 2024, 02:18:12 AM
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Undergraduate General Chemistry Forum / Re: Reverse Diffusion Demonstration
« Last post by Corribus on Yesterday at 08:51:57 PM »
If the tank was hermetically sealed and it is not pressure rated, then, sure, gas generation at the electrode could certainly cause failure.
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Undergraduate General Chemistry Forum / Re: Reverse Diffusion Demonstration
« Last post by S_Ch_S on Yesterday at 06:25:27 PM »
May I ask something: I did the sodium chloride infused water electrolysis in a self-built thin and long water tank for about 3 hours and after I turned the voltage (12V) off, my glass water tank broke. I didn't see how this happened but I found it broken 5 minutes after I turned the voltage off. Any explanation on this? Was the hydrogen product trapped in the water tank but which other factor contributed to this? Thanks!
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Biochemistry and Chemical Biology Forum / Re: Glucose Mutarotation
« Last post by Babcock_Hall on Yesterday at 09:55:26 AM »
https://cdnsciencepub.com/doi/pdf/10.1139/v73-085#:~:text=The%20mutarotation%20of%20glucose%20is,is%20not%20known%20with%20certainty.

You have asked more questions than I can answer.  The beta-anomer is only slightly more stable than the alpha-anomer; therefore, the equilibrium between them is only about 64:36.  Regarding rates of reaction in water, specific acid catalysis is the speeding up of a reaction due to protons.  The definition of specific base catalysis is analogous.  General acid catalysis is the speeding up of a reaction in the presence of a weak acid at constant pH, and the definition of general base catalysis is analogous.  The paper above may answer some of your questions.
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Biochemistry and Chemical Biology Forum / Glucose Mutarotation
« Last post by Aurt on Yesterday at 03:47:47 AM »
Hello. I have been having issues regarding mutarotation of glucose. I've looked up several sources on the internet regarding the interconversion of α-glucose to β-glucose and vice versa (even tried chatgpt), but the most i come up with is "yes it happens". So now I am kind of stuck at one point going round and round about it.
So without further delay... My question is basically regarding the fundamental chemistry of glucose in terms of opening and closing the glucose structure on addition of it to water. The web states that mutarotation takes place in order to maintain equilibrium...but it fails to pinpoint exactly why both forms of glucose are even required (especially when β form is more stable).
I have discerned that this whole phenomenon primarily has to do with the linkage between the anomeric carbon and the 5th carbon in the molecule, namely the hemiacetal bond or glycosidic bond forming the cyclic structure.
I am interested in detailed chemistry behind that particular bond itself, and as to how water is factor in breaking and joining the cyclic structure. Does it also have to do with the aldehyde group in the linear structure that forms the hemiacetal in glucopyranose?
Also protonation and deprotonation of the solution results in increasing rate of mutarotation as well. But in case of extremely alkaline conditions they structure also breaks down or changes to other molecules like galactose or fructose. So is there a certain threshold in alkalinity where glucose can be stored without changing the rate of mutarotation or possibly degrading/deforming the structure?
With all due respect I am not exactly looking for a bookish answer. I am exclusively looking to increase my own knowledge regarding this, so anyone kind of to reply please feel free to use your own words however convenient.
Thanks a lot!
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Undergraduate General Chemistry Forum / Oxygen dip in ionization energy why?
« Last post by sd79812 on May 23, 2024, 11:46:54 PM »
How does spin-orbit splitting also affect this or anomalous zeeman effect or decrease in spin when you move from Nitrogen to Oxygen?

Bad Teacher: The addition of the second electron into an already occupied orbital introduces repulsion between the electrons, thus it is easier to remove. that is why there is a dip in the ionization energy.

Bad Teacher: In oxygen, the last electron shares a doubly occupied p-orbital with an electron of opposing spin. The two electrons in the same orbital are closer together on average than two electrons in different orbitals, so that they shield each other from the nucleus more effectively and it is easier to remove one electron, resulting in a lower ionization energy.[2][14]

The problem is then you can't use the same explanation to explain Fluorine is higher ionization energy than Oxygen because you're also adding repulsions.

Bad Teacher:Stability of half-filled orbitals or completely filled orbitals.

This quote is using is arguing a point not building evidence for it.

I've tried studying spin and that doesn't explain it.

I tried using term symbols. Can you compare ionization energies of different atoms using that via Highest spin highest J?
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Generic Discussion / Re: Human Hormones Emulators and Disruptors
« Last post by Babcock_Hall on May 23, 2024, 03:53:18 PM »
https://pubmed.ncbi.nlm.nih.gov. This is the link to the search engine PubMed.
https://www.healthline.com/nutrition/what-is-bpa

Hi Maads,

I don't know the specific answers to your questions.  However, I have a few suggestions regarding how you could go about learning.  The most important thing is to avoid pseudoscience.  If you want to read in-depth, journal articles, I recommend only reading articles that are peer-reviewed.  If you use PubMed as a search engine, I suggest asking only for review articles (not the primary journal articles); there is a box that you can check on the lefthand column when you do a search at PubMed which limits your search to review articles only.  You can use Boolean operators in your searches.

Even review articles can be challenging to read.  Therefore, my suggestion is to use reliable, non-journal sources.  Here are a few that come to mind:  WebMD, In The Pipeline (Derek Lowe's blog at Science), Medscape, Mayoclinic.org, Healthline, and Johns Hopkins Medicine.  I am sure that there are many more.

BPS is bisphenol A.
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Generic Discussion / Human Hormones Emulators and Disruptors
« Last post by Maads on May 23, 2024, 03:15:43 PM »
I am trying to understand something i had red on several sources about hormonal imitators in humans.

I had learnt that many new cooking appliances are now sold as "BPA Free" since that substance is said to imitate estrogen, the female hormone.

i also have Asperger syndrome, i am male, i had took knowledge about a theory claiming we use to have extremely male brains after the, likely, pre-birth exposure to either abnormally high ammounts of testosterone or some sort of testosterone emulator in the environment.

I am not a chemist, my fields are robotics, electronics and some coding, however, i feel seriously concerned about  this information, so i would like to ask if someone could help me understand it better, should i be understanding this properly, i would like to ask if it does exist, for example, some sort of list of suspected or probed hormone emulators.

Just let me thank you for your attention and support.
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High School Chemistry Forum / Re: Do paired electrons share the same radial distance (r), polar angle (θ), and az
« Last post by Borek on May 22, 2024, 03:54:30 PM »
You do understand electron doesn't occupy a point in space?
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High School Chemistry Forum / Re: Do paired electrons share the same radial distance (r), polar angle (θ), and az
« Last post by sd79812 on May 22, 2024, 02:26:08 PM »
The nucleus is the point of reference in my spherical coordinates.
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High School Chemistry Forum / Do paired electrons share the same radial distance (r), polar angle (θ), and az
« Last post by sd79812 on May 22, 2024, 02:24:44 PM »
 Do paired electrons share the same radial distance (r), polar angle (θ), and azimuthal angle (φ) where the nucleus is the center?
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