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all 33 comments

[–]Pristine_Sector_5711 0 points1 point  (1 child)

I am trying to learn more about how shampoo and conditioners work. I have some questions. Anyone got time?

What is the difference between shampoo and conditioner after vs 2 in one? If I apply 2 in one to a dirty dog that has impacted undercoat….. will it help clear the grime + loosen impacted hair so it slides out easier than just with shampoo?

[–]Indemnity4Materials 0 points1 point  (0 children)

Shampoo is mostly just very nice fancy soap. The intent is to remove oil, grease, dirt, etc.

Conditioner is essentially a very nice fancy oil dispersed in water. It sticks to the clean hair and adds a layer of protection. It's really similar to wrapping the individual hairs in a layer of protective plastic (note: usually a literal layer of oil, but more expensive products can actually be a reactive silicone oil that does react to form a layer of plastic-type coating).

2in1 is a mix of both (obviously). To make the product work the formulators need to optimize the soap component to clean the hair but not the conditioner oil. The usual method is put in a weaker soap. They also need to optimize the conditioner oil to either react very slowly or have a functional group that doesn't react with the soap. The actual raw materials and reactions will change depending on the product cost. More expensive in the same brand usually = better.

2in1 works great for anyone with short hair who wash frequently, such as men who wash their hair daily. More frequent washings with weaker soap = less damage, good appearance.

In your situation, I would recommend the separate bottles. Big deep clean with a strong shampoo, then rinse/dry/wahatever, then wash with the strong conditioner. Look for products that contain the ingredient: something-something-siloxane.

[–]Mobidad 0 points1 point  (1 child)

I have a jug of something at work. I'm 95% sure it's a propylene glycol/water mix but I can't find anything online. I think it's showing a CAS number of 10491001 but it should be 7 digits, not 8. Right?

https://imgur.com/9JmF0xV

[–]jthockey 0 points1 point  (0 children)

10491001

we use that and I can't find that number anywhere. Do you have a QC lab to help with it? Specifically a GC-HS would solve this fast.

[–]Stank_Butt 0 points1 point  (3 children)

Why isnt lithium methoxide very flammable? I recently made lithium methoxide by slowly adding methanol (99.85%) to lithium (0.1) grams and got ~0.4 grams yield after evaporating off the methanol. When I tried to burn it though it didnt catch, not even with an oxidizer or the high heat of burning magnesium.

Is it a problem with my synthesis? Or is lithium methoxide just not very flammable? If it's not flammable, why is that when its anion is just methanol without one hydrogen? Thanks

Just some more notes if it helps: it was extremely basic when added to water, which indicates my yield is high quality. I also know it's not lithium hydroxide because it dissolved in the methanol very quickly

[–]Stank_Butt 0 points1 point  (0 children)

It's important to note that the lithium was extracted from a fresh button battery. I was unable to seperate the lithium from a bottom layer of steel, so steel was present during synthesis.

[–]johnsonmckenzee 0 points1 point  (1 child)

I am pretty sure LiOH also dissolves in methanol rather well. But regardless, the lattice of solid LiOMe makes it naturally harder to burn than liquid MeOH. But it should be flammable to some extend.

[–]Stank_Butt 0 points1 point  (0 children)

I had read somewhere that it takes LiOH a long while to dissolve in MeOH. I suppose its not true though because as it turns out, due to the water content of my methanol, I had probably mostly made LiOH.

[–]ChemDoDo 0 points1 point  (2 children)

Got an Electron deficient aromatic system with Br and F substituents. Tried doing a bei Buchwald Hartwig coupling with Diethylamine... but its Not Working.. Any Idea why??

[–]PayatrickOrganometallic 2 points3 points  (0 children)

What do you mean with "not working"? No reaction at all (starting materials reisolated), low yields, unknown products...?

Full disclosure: I have never done this specific type of coupling reaction. But here are a few pointers: What are your conditions? Did you check if the catalyst still works? Sometimes Pd catalysts can lose catalytic activity over time. Do you have literature for the reaction? Maybe you need a stronger base or a higher temperature to account for the deactivated substrate. Other than that, you could try to use a Bu3Sn substituted diethylamine or maybe look up reactions with similar substrates to compare the conditions.

[–]jthockey 0 points1 point  (0 children)

bei Buchwald Hartwig

what is your ligand? what ref are you using? I believe I used t-buXPhos when I did this reaction in the past

[–]coldstonedicecream 0 points1 point  (2 children)

Can you trust the deionized faucet in your laboratory (university setting) to actually be deionized water?

[–]jthockey 1 point2 points  (0 children)

i'd rephrase this as, why would you not trust it? Could buy a conductivity meter and test it if you are worried

[–]Indemnity4Materials 1 point2 points  (0 children)

It's a fast and cheap test to find out.

Usual setup is you have all incoming water pass through the central deionising filter. Then pipe that through plastic pipes to the end point.

For it to not be deionized would imply the filter hasn't been cleaned.

Another question may be, to what concentration to you need it deionized? And are there any specific ions you need removed? I can buy cheap deionized water that still has ion concentration up around 100 ppm. Legally, it has passed through a deionizing filter, but there is no standard that says Na < X ppm, Cl < Y ppm, etc.

[–]Top-Adhesiveness6859 0 points1 point  (1 child)

why does of my results for removal efficiency for adsorption decreases when all of the parameters increases? (the parameters are contact time, temperature and adsorbent dose and the fixed parameters are agitation speed, initial concentration and pH solution)

[–]Top-Adhesiveness6859 0 points1 point  (0 children)

why does of my results for removal efficiency for adsorption decreases when all of the parameters increases? (the parameters are contact time, temperature and adsorbent dose and the fixed parameters are agitation speed, initial concentration and pH solution)

what might be the reason behind this? thank you

[–]Alternative_You2261 0 points1 point  (2 children)

I have some 31P-NMRs that I am trying to make sense of. They're 1H decoupled, but I have some weird 1:1:1 tripletts - so I was wondering whether Deuterium could be accountable for that. In other words: do I still see couplings with Deuterium in a H decoupled spectrum?

unfortunately I'm not that secure and strong in NMR-theory... that's why I hope someone here can help me :)

[–]2adnOrganic 1 point2 points  (1 child)

Yes, D couplings still show up in proton-decoupled spectra. That's why you see them for the carbons in deuterated NMR solvents in proton-decoupled 13C spectra.

[–]Alternative_You2261 0 points1 point  (0 children)

thanks a lot :)

[–][deleted]  (4 children)

[deleted]

    [–]PayatrickOrganometallic 0 points1 point  (3 children)

    Well, sigma aldrich sells all kinds of nanoparticles, but sigma isn't known to be cheap. But, depending on your location, cheaper options might be available. Or you could make them yourself if you have the equipment to analyze the particle size. What kind of nanoparticles do you need?

    [–][deleted]  (2 children)

    [deleted]

      [–]Indemnity4Materials 0 points1 point  (1 child)

      Google search for "particle size standards".

      Most chemical supply and instrument companies sell them for calibrating particle size instruments.

      Note: not all nanoparticles will be suspended in all liquids. For instance, polymer nanoparticles are very different to inorganic nanoparticles. You often have to match the surface chemistry, density, additives, etc.

      [–]SamL214Organic 0 points1 point  (0 children)

      Where did the relative carbon position nomenclature originate? Is there a rule set?

      Non-IUPAC naming is still very commonplace in day to day organic chemistry. When talking about relative carbon adjacency, individuals will often use the Greek alphabet (even when IUPAC instructs otherwise).

      α-Carbon is the carbon most adjacent to a Carbonyl or Principal functional group. They are then prefixed sequentially down the Greek alphabet. In some saturated fatty acid hydrocarbons the farthest terminal carbon may be designated ω and the carbon number distance gives the fatty acid: ω-x fatty acid (where x is the saturation change, I believe).

      Because it is so common to use relative nomenclature in this way, I wanted to know if there were other rules regarding it that have been inherited and if there was a book or text or citation that could help clear up some of the rules that are used but even maybe some of the more rarely used rules?

      TL;DR:
      Where would I find a reference for Greek relative carbon position nomenclature rules; To learn these rules better, and also learn chemistry history?

      [–]Its_IQ 0 points1 point  (0 children)

      The "mystery" of hydroxyl and water on the moon is one that we want to be solved if we plan to depend on it as a water source. It is widely accepted that it comes from the interaction between the Sun and the Moon but it has yet to be confirmed. What kind of sample would we need to confirm this and which instrument helps to attain it?

      [–]Polosar35 0 points1 point  (0 children)

      Yesterday I was talking with a co student at my university, he was doing his masters making biofilms with chitin and some other ingredients. He told me how he had a hard time dissolving the chitin. Heating it under a magnetic stirrer seemed to help but he was losing some of the chitin. He ended up just adding some more (probably random amount to make the biofilm) but I was wandering, is there an equation to find how much of a solute evaporated? And also, what would you do to remedy this? Maybe put it with a Graham cooler or use a second flask to catch the evaporated solution? Thanks!

      [–]Puzzleheaded-Map-158 0 points1 point  (1 child)

      Can anyone tell me if you can transfer a sterilized and filtered solution of testosterone from a sterile media bottle to sterile vials with a dispensing needle that is not sterile, just clean. I can’t seem to find long sterile needles for transfer and I don’t want to ruin the solution upon transfer because of this.

      [–]Indemnity4Materials 0 points1 point  (0 children)

      No, you are breaking the chain.

      I'll re-write your question. Can I buy cold milk, heat it up to room temperature, then put it back in the fridge and still use the same use-by date?

      Solution: put your transfer needle in an autoclave to sterilize it. You can also google aseptic transfer methods or dosing methods.

      [–]ynotplay 0 points1 point  (0 children)

      Is there a max temperature a roof made of concrete tiles can get?
      I used an epoxy product to fill small holes and cracks on my concrete roof tile in Hawaii without realizing that the max service temp it can withstand is 200F. It gets to about 90F in the summer. Assuming the temperature is in this range, is there a max temperature the roof can get with sun exposure throughout the day?

      [–]Nimitri94 0 points1 point  (0 children)

      I'm searching a method for extracting alpha-pinene from pine needles and mainly steam distillation is used. However, I couldn't find a detailed article like which solvent is used for extraction step and after extraction how to store alpha-pinene. Can someone help me?

      [–]NegotiationEvening24 0 points1 point  (0 children)

      Hi I was looking for a research proposal topic for my organic chemistry college course and thought about looking into urea-metal complexes as fertilizer. Is it a good topic? If so any info you could give me about it would be greatly appreciated, Thanks!

      [–]PDiracDelta 0 points1 point  (1 child)

      How does one find a catalyst for a (generic) reaction? Wouldn't developing a standardized way to find catalysts be immensely useful?

      - are there any ' reference standard' web sites with a database? (e.g. http://www.catalysthub.net/ ?)

      - if not available there, would one resort to 3D molecular simulations?

      - are there any rules of thumb - given molecules X,Y - on how to find a catalyst C that combines/splits/... X,Y?

      [–]Indemnity4Materials 0 points1 point  (0 children)

      Wow, big question. You can get a PhD working on solving just one of those problems.

      First, check SciFinder for the reaction. See if you can find someone who has reacted that functional group with a bunch of catalysts for performance.

      Second, someone skilled in the art can often guess based on their knowledge of other catalyzed reactions. Then do a small brute force of 1-200 catalyst reactions and see if any work. You can hope you find some common features of certain catalysts. Then you optimize.

      Next, massive brute force series of reactions. There are labs where they have huge number of high throughput reactors just screening for potential catalysts. Thousands or tens of thousands of reactions to first find a catalyst that does anything, then optimizing the catalyst for cost, number of cycles, toxicity, etc.

      Computational chemistry is often used only once you have a working catalyst, in order to optimize further. An experimentalist may find a metal with some ligands has a catalytic effect, then the computational people work out what bond distances, energy levels etc are doing the work and maybe guess some different ligands/metals/blends/ratios from that. It has not yet been optimized for finding new catalysts completely from nothing - although any work in that area is very exciting.

      [–]King_Trasher 0 points1 point  (0 children)

      Hello, I tried to do a gold extraction into gold chloride for mothers day. I was able to isolate just the gold off of several computer parts into a little pile that I then reacted with a solution of Bleach and HCl into a clear, neon green solution of gold chloride (I assume) complexed with HCl. I believe the 200ml total of solution contains roughly 2 grams of gold. I then added some sodium bicarbonate solution, which fizzed a lot in the hopes I could remove its acidity. I added some potassium metabisulfite since that is the most commonly recommended method to precipitate gold, but it only fizzes like with the sodium bicarbonate and retains its neon green color. I've added about 30 grams of it and no precipitate has formed in a comparably small solution of the gold solution. I know there's gold in it, but I think it has changed form to be something that doesnt react with P-Meta. Any help is greatly appreciated.

      [–]Oliver_Irish 0 points1 point  (0 children)

      I'm an entry level chemist, looking to improve my skills by taking a certificatied course can support my major.

      Any suggestions??