アセトンの熱分解によってケテン単量体を得て、氷酢酸に作用させることで無水酢酸を得ます。 Acetic anhydride is obtained by allowing the ketene monomer obtained by pyrolysis of acetone to act on glacial acetic acid.
Пікірлер: 17
@user-gx2ou6br1v Жыл бұрын
ごちゃごちゃしててかっこいい
@will_der_dude Жыл бұрын
...you make it look so easy! ty
@Nikon734 жыл бұрын
アセトンを入れる時にプラ瓶に入っていた白いつぶってなんですかね?
@luiseduardogonzalezgranado30282 жыл бұрын
ニクロム抵抗器にはどの電圧を使用しましたか
@user-zb7ep7uu8g Жыл бұрын
質問です! アセトンの容器に入っている粒々はなんですか?
@okay86323 жыл бұрын
Could the acetic acid be 90%? What effect will 10% H2O have on the ketene/reaction?
@chemistryofquestionablequa62523 жыл бұрын
Ketene will convert the water to acetic acid first, then acetic anhydride production will begin. In short, you'll need more acetone.
@psycronizer2 жыл бұрын
technically, you COULD use 90 percent, sure, the ketene will first react with that water to form acetic acid, then when no more water is present it will acetylate the acetic acid, forming the anhydride. The issue however is that you increase the likelihood of polymerization products with water present, it is better to use dry acetic acid. Glacial. Otherwise, you will have to remove contaminants with distillation.
@user-uo8fj9xn1q2 жыл бұрын
アセトン自体を加熱するだけでは、ケテンには至らないのでしょうか? 実際何度必要ですか?
@yuki40403 жыл бұрын
多分塩化カルシウムじゃないかな?
@fmgkk37073 жыл бұрын
ケトンに塩化カルシウムは使えないから、水酸化ナトリウムあたりじゃないかな?
@luiseduardogonzalezgranado30282 жыл бұрын
あなたに連絡する方法があります私はあなたにプロセスについて話したいです
@psycronizer2 жыл бұрын
The process is of course not 100 percent efficient, you have no real way of knowing exactly how much ketene is making it into your acetic acid. Which is why you should have added a known weight and volume of acetic acid, plus the known weight of the flask. If you have a known molar quantity in the flask, then you can periodically stop the process and weigh the flask to check if it has reached the theoretical weight for the molar amount of acetic anhydride. The way this guy has done it is just flying blind. Ketene is very reactive, especially so when it has a long travel path in the presence of light, it can easily polymerize and not just make the anhydride.
@WeebRemover4500 Жыл бұрын
so, increase surface area of bubbles lights off cover flask in aluminium foil 120g --> 204g = 100% yield ive heard 600*C is where it starts to happen, but higher temperature is better? the acetone doesnt seem to be splitting perfectly into ketene
@psycronizer Жыл бұрын
@@WeebRemover4500 all that will help but it won't "split perfectly into ketene" there aren't many reactions in high energy complex chemistry that are 100 percent, there's all sorts of things going on. Think of it like this, at the atomic level, the shape of the electronic fields that are the place where the true interaction begins, those surfaces, or areas, are curved and large, and there is a lot of points along that curved area of field density for attraction and repulsion, this gives rise to the chances of different reactions and thus products to occur, this is especially so with molecules like acetone and ketene, with their carbonyl groups and the alpha hydrogens all offering areas of resonance , higher and lower charge areas, it's actually quite complex what is going on down there at that level, given that level of complexity and high energy you will never get 100 percent yield from this reaction, not ever. With a known quantity of acetic acid, you can keep bubbling in Ketene and periodically stopping the process and weighing your flask with the acetic in it, when it finally gets to the theoretical weight for that molar amount of acetic anhydride, you stop. This way you have converted all the acetic acid that you started with, there will be some minor contamination, which is why you then distill it, then you have your acetic anhydride, as much as possible, and fairly pure.