May 23, 2024, 05:39:11 PM
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Generic Discussion / Re: Human Hormones Emulators and Disruptors
« Last post by Babcock_Hall on Today at 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 Today at 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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You do understand electron doesn't occupy a point in space?
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The nucleus is the point of reference in my spherical coordinates.
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 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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Halbach array. is that any good for understanding why opposite spin electrons, that the magnetic fields actually can cancel in macroscopic reality?
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Analytical Chemistry Forum / Re: Acid chloride TLC
« Last post by Babcock_Hall on Yesterday at 12:42:44 PM »
What is the Rf of the starting carboxylic acid in your solvent?  Do I understand correctly that you are using 2:1 methanol/hexane as the TLC solvent?  I was under the impression that methanol and hexane are immiscible. 
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Hello dear forum members,

I'm new here and I have registered to ask a question which for some reason is difficult for me to solve on my own as I struggle to wrap my head around it. The problem pertains to electrophilic aromatic substitution reactions. I know how it works, both in theory as well as in practice when it comes to monocyclic arenes like benzene itself and how activating/deactivating ortho/para/meta directors decide over at which C-X the next group will be bonded to (please note that "X" here doesn't stand for halogens but is a placeholder for the position number of the carbon in question).
However, things got complicated for me once I moved on to polycyclic compounds because I have no idea how to "jump" back and forth between neighbouring rings. To make matters worse my textbook only explains Se-Reactions in the context of monocyclic arenes like benzene and phenol.

Let's take for example biphenyl. Assuming the Se-Reaction starts at ring A, how does a chemist ensure that his next reaction takes place at ring B? No matter whether I use activating/deactivating ortho-para-meta directors, the reactions will always take place on ring A, right? What does it take to affect the regioselectivity of the molecule in such a way to "jump" to ring B?

Another example would be the phenanthrene molecule (I have uploaded an image with the numbering system of the (4,5-epoxy)morphinan family). This one is different as ring B is essentially a cycloalkene which responds to E1/E2/E1cb-Reactions as well as Addition-Reactions, so I would assume that simply doing one of these reactions automatically removes/adds functional groups to ring B instead of the neighbouring arenes. But what if I am currently at C-3 of ring A after having substituted the H-atom with an OH-group via Se and want to skip ring B and go directly to ring C (which is also an arene that also responds to Se-Reactions) and add another OH-group at C-6? The OH-group at C-3 would be a strongly activating ortho-para director, so the next reaction will take place at either C-2 or C-4 (ring A). Para isn't possible because C-12 doesn't have any valence electrons left (and even if it had any, there is too much steric hindrance, so a reaction at ortho is much more likely).
I can't imagine that a chemist has to go through the entire ring structure and do a whole range of unnecessary and time-consuming reactions until he reaches his desired C-6 position to manipulate. There must be some kind of standard ruleset that chemists apply in order to address specific rings while leaving others alone. Something that gives us more control over the regioselectivity of the reaction we want to conduct.

Maybe the best way to answer my question would be to tell me how YOU would synthesize the compound 3,6-dihydroxyphenanthrene if you were to start with phenanthrene.

I hope I haven't expressed myself in too complicated a manner and if I did I apologize as english isn't my mother tongue. I have really researched book after book, searched websites and sifted through youtube videos but I haven't found anything that discusses how to affect the regioselectivity of a polycyclic molecule in order to conduct reactions at different rings instead of a single ring. Maybe I'm thinking in overly complicated ways and can't see the forest for the trees anymore. Whatever it is, I need help because this is driving me insane. Thank you.
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Physical Chemistry Forum / Re: Aluminium-Copper battery
« Last post by Borek on Yesterday at 09:29:57 AM »
First thing to check: concentrations and potentials as calculated from the Nernst equation.

Then: Al is a poor choice in general. It gets quickly passivated with the oxide, so you don't have an Al/Al3+ system in your cell (ie. metallic Al is not able to directly oxidize to Al3+ and move into the solution). That means theoretical predictions based on the standard electrode potentials are useless.
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Physical Chemistry Forum / Aluminium-Copper battery
« Last post by hartalinstalin69 on Yesterday at 05:48:13 AM »
Chemicals used:CuSO4(aq), Al2(SO4)3, KNO3(salt bridge), copper and aluminium electrodes.

Hi, i recetly made an experiment based on electrical potencilas shown in link below, i was thinking that it at least seems to be better thant classic zinc-copper battery (potencial of 1.1V) becase it should have more voltage maybe (based on the potencilas it should had been aroud 2V) but in reality it is just around 0.5V.
Why is that???


2 e + Cu2+   ⇌   Cu(s)   0.337V
3 e + Al3+         ⇌       Al(s)        -1.662V
the link:https://en.wikipedia.org/wiki/Standard_electrode_potential_(data_page)
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