please share link for ios system crack version of chemdrw
@marsnomad33713 жыл бұрын
thank you it's very helped me
@jonathanshved3 жыл бұрын
Like watching paint dry, beautiful
@edis94934 жыл бұрын
Thank you
@hazeljacob134 жыл бұрын
bad job
@alexandery85084 жыл бұрын
Was the goal to find concentration OH and H30? you did know the base constant = 1.8 x 10^-5. So, what then? i didn´t follow
@rachelmaawad28084 жыл бұрын
Hey girl, just wanted to say that I love your videos so much! They have been so helpful in organic chemistry II and I honestly plan on getting an A on this Friday's exam because of these videos. I will update you soon! Have a great night.
@foifoifoi6106 жыл бұрын
THANK YOU SO MUCHH
@DotaMaster3216 жыл бұрын
but what about quiz, misleading title
@Dualies8 жыл бұрын
Can you provide a reference for this mechanism?
@maryamlatif37338 жыл бұрын
Thanks for this! My teacher took a whole class period to explain this, and it still didn't make sense. You clarified in 32 second :)
@tigerdogmom9 жыл бұрын
cannot hear anything.
@chemistrycentre81709 жыл бұрын
Sometimes it's difficult to make out what you're trying to show with your arrows, like the one where the N is being deprotonated in the third step.
@chemistrycentre81709 жыл бұрын
Maybe you should consider using an iPhone earbud/microphone. It would make it easier to hear your narration instead of the background noise (mostly that loud teacher).
@chemistrycentre81709 жыл бұрын
If you are using Explain Everything, you should be able to zoom in and out on the screen. It seems that you weren't aware of that feature. If you're using Doceri, you do not have unlimited screen real estate. I can't tell from what's written here which app you were using.
@chemistrycentre81709 жыл бұрын
Whoa! You said that you know the rate law is first order because the graph was linear. You didn't mention what was graphed. The question on the handout said that [C2H5OH] vs time was graphed. That graph being linear suggests the reaction is zero order, not first order. So you used the wrong equation to determine the concentrations.
@chemistrycentre81709 жыл бұрын
It seems like you considered 150 s to be two sig figs. I considered it as 3 sig figs when I wrote the key. Unfortunately the way the problem was written, the number of sig figs is ambiguous.
@chemistrycentre81709 жыл бұрын
It's a little tough to hear your voice over all the background voices. Maybe you could use one of those microphone headsets.
@chemistrycentre81709 жыл бұрын
Maybe it would be better if you wrote some parts ahead of time before you start recording. I know it's difficult to write and talk at the same time.
@chemistrycentre81709 жыл бұрын
It would be nice if we could see something while we hear your voice. It's a little disconcerting for the screen to stay black for the first half minute and then go black again.
@mazbazooka9 жыл бұрын
The words are not legible on the handout in the early part of your video, unfortunately.
@chemistrycentre81709 жыл бұрын
Make sure you always show the negative charge on the base!
@chemistrycentre81709 жыл бұрын
It would be nice if you would explain the mechanism as you draw it.
@chemistrycentre81709 жыл бұрын
The first two steps of your mechanism are perfect. But after your first alkylation, the negative charge is now on the bromide rather than the alkyne. In order to carry out a second alkylation step, it is necessary to react the alkyne with another molecule of base.
@chemistrycentre81709 жыл бұрын
Your product is perfect. Your depiction of the transition state suffers because it's awfully hard to depict partial bonds and stereochemistry with the same set of lines. I encourage you consider drawing the structure so that the partial bonds can be right in the plane of the page. That way you can show the partial bonds with dotted lines. And you can show relative positions (stereochemistry) with positioning on the page.
@chemistrycentre81709 жыл бұрын
You guys should speak up! I can barely hear you above the voices of others in the room.
@chemistrycentre81709 жыл бұрын
Methanol (your solvent) is not acidic, so you will not have an appreciable amount of methoxide (CH3O-). It's less acidic than water, which has 1E-07 M hydroxide for a neutral solution. Instead of using methoxide as the nucleophile, you should be using methanol as the nucleophile. That means the structure formed after the carbocation will have a positive charge on the oxygen, which has three bonds. It also means you'll need an additional step, to deprotonate that oxygen and give a neutral product.
@chemistrycentre81709 жыл бұрын
The stereochemistry on your carbocation intermediate is not shown appropriately. The carbon with the positive charge is planar, so the methyl group should no longer be pointed back.
@chemistrycentre81709 жыл бұрын
Too bad that woman in the background talks so loudly.....
@chemistrycentre817010 жыл бұрын
I'm not sure why your video started with the swirly doodle before you got to your naming example. Nice job showing that you understand the naming rules.
@chemistrycentre817010 жыл бұрын
Great job demonstrating your understanding of the nomenclature rules. It can be a little tricky when you try to draw the t-butyl substituent when it's not attached to anything. In your example you added another carbon, and then you had 2,2-dimethylpropane rather than a t-butyl group. We don't have a nice way to show things as groups unless we attach them to other bigger molecules.
@chemistrycentre817010 жыл бұрын
That approach certainly helps me spot my own mistakes. ;)
@chemistrycentre817010 жыл бұрын
I like how you numbered the carbons to keep track of them.
@chemistrycentre817010 жыл бұрын
You should be referring to Michael donor and Michael acceptor rather than electron donor and electron acceptor.
@chemistrycentre817010 жыл бұрын
Nice explanation of the mechanism for your Michael reaction.
@chemistrycentre817010 жыл бұрын
What other reducing agents could you use to reduce the nitro group to an amino group?
@chemistrycentre817010 жыл бұрын
The arrow you have when water is leaving is backwards. The oxygen takes the electrons from the C-O bond when water leaves.
@chemistrycentre817010 жыл бұрын
I don't hear any narration during your video, even with my volume turned all the way up. You should speak up a bit when you describe your reaction!
@chemistrycentre817010 жыл бұрын
I love the use of the laser pointer to bring the viewer's attention to the changes in the reaction that you are describing.
@chemistrycentre817010 жыл бұрын
Nice mechanism. It was cool to see your starting material converted to the enolate ion that reacted to form the ring. Remember when you draw mechanisms for tests, you need to show both the enolate and the neutral starting material as separate and distinct structures.
@chemistrycentre817010 жыл бұрын
You should include a second arrow for the ring-closing nucleophilic attack, showing that one of the two carbon-oxygen bonds in the carbonyl group breaks when the nucleophile attacks.
@chemistrycentre817010 жыл бұрын
Some of those arrows have the pen setting so broad that it's tough to see the bonds after the arrows get added.
@chemistrycentre817010 жыл бұрын
I was worried we wouldn't get to see the diacid product formed when permanganate oxidized the two methyl groups, but you showed it!
@chemistrycentre817010 жыл бұрын
It seems that you missed the alkyl groups on the acid you show before the decarboxylation.
@chemistrycentre817010 жыл бұрын
I think you should have called this video the acetoacetic ester synthesis rather than acetic ester synthesis. Hopefully the handout didn't have that mistake on it.....
@chemistrycentre817010 жыл бұрын
You confused me by calling the final step of the synthesis your first step. Otherwise everything looks great!
@chemistrycentre817010 жыл бұрын
In your first step, you talk about making a ketone. But your structure shows an aldehyde, without the methyl attached to the carbonyl. The reaction should work okay whether the carbonyl has a hydrogen or methyl group attached. At the end, you snuck that methyl group back in there, changing the substituent to an ethyl group. Be careful with counting your carbons!
@chemistrycentre817010 жыл бұрын
Nice work with the laser pointer in Explain Everything!
@chemistrycentre817010 жыл бұрын
Nice use of the laser pointer in the app! Too bad that teacher talks so loud while you're recording your videos. In the final step you talked about the decarboxylation. But you didn't mention the ester hydrolysis that you also showed.