Hi Mona, 

We kindly ask to keep the comments relevant to what is discussed in the video. Our subject experts only respond to questions about what is in the video and unfortunately do not answer questions outside of this. But we do have videos on NBS that you can check here:

We do plan on having downloads available, our team is currently working on adding pdfs to go with each lesson video. 

Hi Reine,

Recall a meso compound has chiral centers, this is why an alkene is not a meso compound because it can not have a chiral center since it doesn't have enough groups to do so. 

You're very welcome Suzy! 

Hey Briana,

Here's the answer to this question from our Subject Expert Samantha: 

Several of these above reactions have the possibility of forming E/Z mixtures.

Hydrohalogenation can form E/Z isomers if the reaction is carried out on an internal alkyne. This reaction on terminal alkynes will not form E/Z isomers because you'll end up with two hydrogens on the carbon that was the terminal one.

Hydrohalogenation with Peroxides will form E/Z isomers in any situation (both internal and terminal alkynes).

Halogenation of alkynes using only 1 equivalent of X2 reagent will result in a mixture of E/Z isomers.

All of these situations come about due to the possible ways that molecules can approach each other in the transition state of the various mechanisms.

At this time we do not but our team is working on adding this. We'll send out an email once they're available.

Hi Erika,

I'll link up more videos that explain each reaction and have very similar examples:

a) Grignard Reagent  (Timestamps 0:00-13:24)

b) Epoxidation (Timestamp 0:00-5:37)

c) SN2 Reaction , I recommend drawing out the structure to see what type of alkyl halide it is. There are several examples at 34:04)

d) Fischer Esterification (Timestamp 07:42) This combination of a carboxylic acid and alcohol with acid will form an ester. 

e) SN1 and SN2 Reactions of Alcohols (Timestamps 0:00-10:48)

Hi Erika,

I'll link up the videos I recommend that explain how to do each type of reaction needed:

First thing to notice is that we are opening up the ring of that epoxide in structure A to get to B, also we added an OH and 2 additional carbons. 

To open up the ring we need a strong nucleophile and the only option we have for that is in c. You'll find the reaction and mechanism explained in the below video:

Chemmunity Team

Overall Proton transfer is a fundamental process in chemistry where a hydrogen ion (proton, H+) is transferred from one molecule (the donor) to another (the acceptor).

Proton transfer can refer to either Protonation or Deprotonation. 

Protonation adds a proton while deprotonation removes a proton. 

Chemmunity Team 

The loss of the leaving group is an essential step in many organic reaction mechanisms, particularly in nucleophilic substitution (SN1 and SN2) and elimination reactions (E1 and E2). A leaving group is an atom or group of atoms that detaches from the main molecule, taking with it a pair of electrons and thereby stabilizing the overall reaction.

A leaving group is an atom or a group that can detach from the parent molecule during a chemical reaction, leaving behind a reactive intermediate such as a carbocation or a negatively charged fragment.

The ability of a group to leave depends on its stability once it detaches; the more stable it is after departure, the better the leaving group it makes.

Alkyl Halides: Halides such as Cl, I and Br are common leaving groups due to their ability to stabilize the negative charge after they leave.

Water: In reactions where OH− is protonated to form H2O water becomes a good leaving group due to its stability in solution.