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This is a good question. In this case, the Pd catalyst remains on the carbon support which was collected on the Celite. Theoretically, it could be recycled and reused. I haven't tried that since we normally just throw the celite away, but I don't see any reason why you couldn't.

I'm glad you liked it. It was a lot of work, but fun as well.

A good way to avoid this is likely to start with a decent amount of liquid and also to heat slowly so that you don't heavily overshoot the boiling point. You could also remove the heat source after reaching a steady boil (have the beaker clamped or held up by wire gauze on an iron ring).

@@dr.ianmackenzie869 thanks for answering. Evaporating and refilling both are must for my project. So I need automating them

Hi Aleasa, the product is usually a solid, but sometimes if the product is a mixture or if the rotovap bath is fairly warm then it will stay as an oil for a while until it cools down. It is also relatively common for materials to not crystallize under reduced pressure, but then after you remove it from the rotovap and let it air for a little while it starts to crystallize. I hope this helps.

I'm glad you liked it. 1. Just into the head space is fine. 2. We usually just discard the celite into the trash, especially some the amount of Pd used is so small. If concerned, it could go into a solid waste container for disposal with hazardous water. 3. Yes, this is safe as long as kept away from any ignition sources. 4. Yes, this is safe and also probably a good idea since without the purge your head space may remain largely air (since hydrogen is lighter than air) and the reaction may be slow. One final note: the rate of the reaction may depend on how active your palladium source is. You may need to extend the reaction time if full conversation is not observed during the regularly allotted time.

@@dr.ianmackenzie869 Thank you sir

Good question. It is true that if your product is low boiling that it is quite possible to lose some (or all) of it on the rotovap. However, in many cases, the boiling point of the product is much higher than that of the solvent and so it is not difficult to remove the solvent without losing much product. In this case, our product actually ought to be a solid, but if you check the NMR you will see there is still some solvent remaining. I should have left it on the rotovap for a bit longer. Solids will often solidify on the sides of the flask as the solvent is removed, but if it is a bit of an oily solid (or low melting, etc.) then it might only solidify after you remove it from the rotovap. I hope this helps!

This is a good question. Yes, although it is common to generate steam separately and pass it through the sample the current setup is also a steam distillation (you are just generating the steam directly via the distillation).

I am glad you enjoyed it! :)

You are welcome!

13:30, he is purging the reaction flask. Maybe there's no nitrogen because the hydrogenation of ethyl cinnamate is fairly insensitive to contaminants, but idk... Or do you think that there's a risk for a hydrogen explosion by not purging?

Good question! This specific substrate is chosen mostly because of the ease of the reaction and the short time required, rather than the particular value of the resulting product. However, cinnamates and hydrocinnamates (the class of products resulting from this hydrogenation) have uses in the flavor and perfume industries. I hope this helps.

Lollll

Good question! It is a 3mL plastic syringe that has been cut in half. The balloon is then slid over the cut end and sealed with parafilm or electrical tape. The appropriate size of syringe will vary depending on the size of the balloon.

Glad you liked these. We don't normally cover chapter 12 in our lecture course, but chapter 13 lectures are posted. Hopefully chapters 14-20 (or so) will show up later this spring.

Good question! It is not mandatory to have the needle immersed. Most of the time I just have a needle into the headspace and the stirring action helps being it into solution.

Glad you liked it 😊

This is a good question. Normally 1,1'-diacetylferrocene is a deep red while acetylferrocene is more of an orange. Exact colors in solution are always a little finicky depending on the purity of the substance. I hope this helps!

@@dr.ianmackenzie869 okay thank you! Also what does over 100% percent recovery usually mean?

@@nalin9025 Another good question. It isn't possible with truly pure material so usually it means there is remaining solvent (or an impurity) that hasn't been fully removed and is the source of the excess mass.

LOL common mann! This guy is here to teach chem not how to cook

Glad you like it!