March 31, 2020, 07:49:00 PM
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Organic Chemistry Forum / Re: Is benzene an alkyl?
« Last post by chenbeier on Today at 11:54:05 AM »
Phenyl is the aryl, benzene is an aromatic hydro carbon.
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Inorganic Chemistry Forum / Krypton difluoride MO diagram
« Last post by snowcollar on Today at 10:31:57 AM »
I am wondering what the molecular orbital diagram for KrF2 would be. Also what would be the HOMO and LUMO?
I found an MO diagram for the compound and I have attached it. I understand the in-phase an out of phase combinations shown between the p orbitals on F and Kr but I am confused as to what is going on with the other orbitals that are not shown in the picture.
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Analytical Chemistry Forum / Quantitative Analysis GPC
« Last post by permanganate on Today at 09:58:06 AM »
So i'm looking into deformulations of paints and i've noticed that GPC might be a good way to start, considering that i wouldn't have to separate each component of the formulation in order to do quantitative analysis (i would use FT IR if necessary for compound identification then proceed with the tests according to the compound).

Considering that paints formulations are more or less the same (for example nitrocellulose is a very common compound) i was thinking on making a calibration curve for this compound in specific, plotting Peak Area x Nitrocellulose concentration. However, on my research i did not find if the molecular weight affects this peak area or is it only dependent of the concentration of the sample (I'm dont have much knowledge about GPC), because there are NCs of varied molecular weight. I've found a paper but it didn't mention if the molecular weight varies to the detector response or if is it only the sample concentration.

So, is this quantitative method viable? Separating each compound individually and proceeding to techniques like FT IR/GC/HPLC would be better? Also, im looking for the maximum precision in the quantitative analysis.
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Metal is easier, would that work?
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hello all,

I am an artist not a chemist so please excuse me for asking a potentially obvious question.

I am looking for polymers or any kind of 'plastic' that reacts to temperature change. To give you more detail the temperature changes would be relatively minimal - imagine a room getting warmer and colder. But in line with that, the reaction could be relatively minimal too, all I am looking for is a noticeable expansion or contraction of the material.

Is there anything out there that I could find, similar in nature?

Best,
Zoltan
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Can you try different electrolyte?  I recall Baran group among others having some papers about synthetic electrochemistry so you might want to look in there to see what electrolytes they are using.
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The dissociation fraction of O2 is 0.5[O ]/(0.5[O ] + [O2]). Do you see why?

Edit: include a space in [O ] or it gives odd formatting!
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A pressure equalling an energy?

Actually PV.
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High School Chemistry Forum / Re: Back titration of Aspirin
« Last post by chenbeier on Today at 05:35:16 AM »
The NaOH neutralized the acetylsalicylic acid. The remaining NaOH was titrated. With the  consumption 20.82 ml and the molarities you can calculate the amount of NaOH in mol. You also know how much 25 ml 0.113 M correspond. The Differenz is the amount what react with the Acetylacetic acid.
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A pressure equalling an energy?
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