/r/chemistry

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A community for chemists and those who love chemistry

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Notes:

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Past Weekly Topics

/r/chemistry

3,619,900 Subscribers

5

Pharmaceutical/Biotechnology vs Other Industries

What is it like/how does it differ working as a chemist, particularly analytical chemist, in pharmaceutical industries and dealing with biologics to working in other industries, particularly environmental? I currently work in the environmental industry for a non-profit so I wonder what it's like working in the pharmaceutical industry since I see many more, higher paying jobs in those industries. I've heard that they overwork chemists in these industries, possibly requiring overtime often. I'm sure this is a broad question but I'd like to hear other people's experiences. I'm currently looking at what the next step in my career might look like.

2 Comments
2025/02/02
21:26 UTC

0

Is Your CIF Playing Hide & Seek? (AI Might Have Some Answers)

Hi, first post ever so let's see how this goes. We are Edvard and Jan, a couple of new grads from Aalto University majoring in Artificial intelligence. We want to get more into creating material science tools that use AI to solve problems. We have this idea to automate the classification of Rietveld refinement by basically allowing a Deep learning network. We have an idea which is looking promising, and there has been prominent research that shows promise.

  • We wonder what the size of the problem. For example, how many people are using Rietveld Refinement in a month? Any ideas how to estimate this. 
  • Is finding the correct CIF for your XRD data a huge issue? In what cases is this easy, and when is it really hard?

If you do a lot of Rietveld refinement and are interested in testing our proof of concept, the link on our website https://deep-molecule.com/.

https://preview.redd.it/61i670xj6sge1.jpg?width=888&format=pjpg&auto=webp&s=f21574fa35232974418733b4c0a3cd6b7da3ed05

1 Comment
2025/02/02
19:58 UTC

3

Looking for insight on DCM ban and undergrad labs

Hello all,

DCM was recently made more difficult to work with and I teach undergraduate labs. I have been told, and the regulations suggest, that undergraduate labs will only be able to use DCM if all personal are trained, wear monitors, and proper PPE. Of course this is not something undergraduate labs can do and I remember arguing with others recently on a different sub that undergraduate labs were exempt or didn't have to deal with the ban.

Can anyone provide insight into this? If it is allowed, are there sources I can send to our safety officer?

8 Comments
2025/02/02
19:53 UTC

4

Can I ask a chemist to explain fugacity to me (I’m doing chemical engineering )

10 Comments
2025/02/02
18:03 UTC

3

Silver on alucobond artwork - how?

Hi, I was at an art gallery some time ago and there was an artwork which creation process I can’t really grasp and I’m still trying to figure out. The medium is described as “Silver on alucobond” and it results in mirror effect on the composite. I know alucobond is basically a core surrounded by two sheets of aluminum, but where and how does the silver come into play?

1 Comment
2025/02/02
17:38 UTC

7

Why phenol and iron III make such an intense purple complex

Why the color is this intense? And what complex species give it this property? Do other phenolic compounds, such as salicylic acids, form the same complex ratio?

These questions occur to me after doing the famous ferric chloride tests for phenol in my high school lab. The salicylic acid and phenol form a very deep purple solution with FeCl3, while the acetylated product of those produces a colorless solution, the phenolic O must have been the responsible ligand!

I thought the research process was gonna be easy, like 5 minutes of Googling or something and there would be a textbook explanation using MO or CFT, instead what I found was inconclusive.

Old references give conflicting results as to what species are responsible for the color. As ref [1] concludes a 1:1 complex between phenolic compounds and iron, [2] concludes a 3:1 complex,...and thermodynamic studies didn't give me any answer either [3]. I did find some recent papers on iron-catechol complexes [4] but I don't know if that correlates to phenol.

Are my questions flawed in the first place? Am I asking for too simple of an explanation?

I would appreciate any explanation or advice. Thank you in advance.

[1] J. Am. Chem. Soc. 1952, 74, 4, 1013–1016, https://doi.org/10.1021/ja01124a041

[2] Science 118, 327-328(1953). DOI:10.1126/science.118.3064.327

[3] J. Am. Chem. Soc. 1969, 91, 8, 1958–1961. https://doi.org/10.1021/ja01036a016

[4] Bijlsma, J., de Bruijn, W.J.C., Hageman, J.A. et al. Revealing the main factors and two-way interactions contributing to food discoloration caused by iron-catechol complexation. Sci Rep 10, 8288 (2020). https://doi.org/10.1038/s41598-020-65171-1

4 Comments
2025/02/02
15:55 UTC

1

Hypothetical Poison Question

I was watching a show where the main character and her dad were discussing whether or not to allow a poisoned patient to drink water after ingesting poison(tobacco).

Her dad said to not let them drink water because it would dilute the gastric(stomach) acid, which can prevent absorption of poisons, so having them drink water would be dangerous and speed up the absorption of poison in the body; so instead, they had the patient drink a mixture of charcoal and herbs(not sure if this is an aged remedy or actually does anything). I tried googling this and it says if poisoned DO drink water to slow the rate the body absorbs the poison. I wanna also say they mentioned that if the tobacco was dissolved in water before consumed, drinking water would be better and actually beneficial.

Is this right? and what does this mean on a chemical level? Also, what does the charcoal do? pls note this is a historical fiction show so I didn't expect for it to be 100% accurate i was just curious.

0 Comments
2025/02/02
06:35 UTC

0

How does water make gasses potent?

I have a question for you nerds, why do farts smell more potent when they pass through water? I was sitting in my bathtub ripping some big ones and realised my farts have been intensified, they don't smell like regular room farts, these ones smelled more potent, has anyone else noticed this? Then I got to thinking, bongs do the same thing, bong hits are more potent than regular puffs of smoke. Shouldn't filtering something reduce the potency, I wonder what the principle behind the phenomenon is.

15 Comments
2025/02/02
13:07 UTC

1

Good optical spectral analyzer in Europe?

Hello,

I was wondering if somebody here know what the most relevant optical spectrum analyser would be (from UV to IR) to measure the light emitted by welding light, magnesium combustion,… with a fast refreshing time (more than 5 Hz I would say).

Thank you in advance!

0 Comments
2025/02/02
09:22 UTC

2

Incorrectly mixed CMC powder with water and formed clumps

I tried to prepare some wallpaper adhesive by incorrectly putting a lot of CMC powder directly into water. A lot of clumps have formed. I've tried to get rid of them by trying to break up the clumps with my hands, but the clumps haven't dissolved. What can I do to make them dissolve? If it's not possible, then how can I get rid of the clumps safely?

3 Comments
2025/02/02
08:44 UTC

2

How can some smells travel instantly?

When I'm in my room upstairs and they make coffe in the kitchen downstairs, I can immediately smell coffee. The kitchen is even far from the stairs and so is my room. As soon as I hear the sound of the coffe maker starting to pour coffee in the cup, I also smell coffee. How is this possible? It's not even ventilated, it's winter so all the windows are closed. Air isn't even circulating. But since smell is molecule-induced, there's definitely some physical matter travelling here.

I noticed this is more common with food smells, especially when cooked.

13 Comments
2025/02/02
08:40 UTC

10

Mechanism with acetonitril

Hello all. I am reading this article about reduction of ketone to alcohol using electrochemical approach. And I bumped into this mechanism with water as a hydrogen source. They mentioned that when they used MeCN, the reaction went smoothly with a high yield.

I just wonder that if they use MeCN, can we explain the mechanism as the one they proposed with water. Because I think the strong of C-H in MeCN is hard to break to have the same mechanism?

4 Comments
2025/02/02
08:28 UTC

1

Any suggestions?

I need to kill bamboo tree in my father's farm. Can I get any herbicide suggestions for it?

1 Comment
2025/02/02
07:32 UTC

8

Dehydrozingerone

4 Comments
2025/02/02
06:22 UTC

0

What is the most effective way to measure the rate of reaction of different catalysts in a transesterification reaction to make biodiesel from vegetable oil?

2 Comments
2025/02/02
04:55 UTC

97

R.I.P.

33 Comments
2025/02/02
04:02 UTC

2

Bruker Opus software for Sentarra II with joystick

I purchased a Bruker Sentarra II Raman microscope used. It is complete except for the software. I've been dealing with Bruker for 18 months, and I am getting nowhere. They don't seem to want to sell me the software. Any ideas on how to obtain software?

2 Comments
2025/02/02
02:03 UTC

3

Gringard

If I have a gringard that's refluxing and I don't have time to make the addition of the solution to the electrophile, is it a problem to just leave it refluxing overnight so I can use it The next day. Typically the gringard is ready after 1-2hrs. The arylbromide for the gringard is 1-bromo-3,5 di-t-butylbenze.

1 Comment
2025/02/02
00:50 UTC

50

Big name politicians with a chemistry background

  • Xi Jinping, president of China
  • Angela Merkel, former chancellor of Germany
  • Margaret Thatcher, former PM of UK

So if you want to go into politics, change history, do chemistry?

43 Comments
2025/02/02
00:32 UTC

1

contaminated water with flexographic ink

How can I treat water contaminated with water based flexographic ink? I've been trying to treat it for a long time, but aluminum sulfate doesn't precipitate it.

0 Comments
2025/02/01
23:45 UTC

1

Book recomendation for alcohols and ethers

Hello, I'm studying for an exam that covers alcohols and ethers (Organic Chemistry 2). My school uses Wade's book, and I've been doing some exercises from McMurry, but I'd like to practice more. What books (available in PDF) would you recommend for this purpose? (Intermediate level) Thanks!

1 Comment
2025/02/01
22:44 UTC

1

Synthesis Help

Hi! Im looking to cleave 2,2'-biquinoline right in half at the central C-C bond to end with two quinolines. Does anyone have any ideas on how to do this?? TIA

https://preview.redd.it/dhf58chhulge1.png?width=329&format=png&auto=webp&s=ddf11d2e5e29f1ab41cfd588877de46242e5cfa1

1 Comment
2025/02/01
22:36 UTC

3

Iron crystals by electrolysis of anhydrous FeCl₃ in non-aqueous solvent?

I got to thinking back on one of my high-school lab exercises on electrochemistry. A zinc/copper cell was set up and left for several days, which resulted in the growth of some rather pretty copper crystals. (And disappearance into solution of zinc, of course, with some black particles which I tentatively attributed to carbon contaminating the zinc.) Which led me to wonder about growing other kinds of metal crystals. Similar setups can be used to grow silver crystals, of course, and I wouldn't be surprised to learn about doing it with gold.

Other metals wouldn't be so easy because of their electrochemical potentials and competing reactions. If I tried to electrolyse iron-containing solutions in water, I'd expect to get hydrogen gas rather than iron. But perhaps in non-aqueous solution? Might it be possible to get iron crystals by electrolysis of, say, anhydrous FeCl₃ dissolved in anhydrous alcohol or acetone? "Spectrophotometric Studies of Iron(III) Chloride in Nonaqueous Solvents" (Russell S. Drago, David M. Hart, and Robert L. Carlson, JACS 87:9 1900, May 5 1965) indicates that there's dissociation of the FeCl₃ in MeOH and DMSO, so there would be ions to migrate.

There would probably be a market for genuine "cold iron", which had never been exposed to heat at all, among purveyors of woo. :-)

0 Comments
2025/02/01
20:58 UTC

2

Previous owners lefts a bottle of nitric acid.

Is there a household use for Nitric Acid? If not, what do I do with about half a liter of it? Can I throw away?

If this isn’t the right place to ask, what subreddit can help?

28 Comments
2025/02/01
20:56 UTC

141

Does anyone else feel like hydrophobic molecules are the enemy?

Since I started learning about polar and non-polar molecules in middle school I have always felt disdain towards hydrophobic/non-polar molecules (like fatty acids, but saturated fatty acids are less evil than unsaturated). I feel like the polar head group on the phospholipid is on my side but the tails and everything else inside of the membrane are out to get me. Does anyone else feel this?

70 Comments
2025/02/01
19:40 UTC

0

Bleach and temperature

Hi there. I’m wondering how effective bleach is at sanitizing for viruses in cold temperatures? I see many things online that suggest it degrades in sunlight or temps over 70 degrees but I’m not sure about cold. For example, if I have an object in my yard I wanted to disinfect and it’s below 40 degrees outside or was even colder prior to reaching a high of 40, will applying bleach to a cold item stop the effectiveness of the disinfection and sanitization the sodium hypochlorite is designed to do?

Thoughts?

Could one test the effectiveness of bleach in cold with pH strips?

8 Comments
2025/02/01
19:31 UTC

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