I was curious about the chemistry of what’s going on while I’ve been wiping tobacco tar off the walls of a house with trisodium phosphate solutions. Pretty cool.
In the second structure of the mechanism, could anyone explain why -OR would leave instead of -OH? If -OH is a bad leaving group (which is true), isn’t -OR in general an even worse leaving group?
Its because while -OH is a bad leaving group, -OR should be a better leaving group. As the electron from the charged oxygen goes back to the carbon to reform the double bond, the electrons on each one of the other oxygens have to make a choice as to which one will go to their respective oxygen and leave. Think about -OHH. This is an excellent leaving group. Why? It is because when the electrons go to the -OHH group, it forms H2O which is a super stable molecule. Think about the electron negativities of oxygen, Hydrogen and carbon. While oxygen wins at 3.5, C comes in 2nd at 2.5 and H comes in third at 2.1. When an O has one H on it, the pull from the hydrogen is not enough. When there are two hydrogens, the pull is strong enough to make it an awesome leaving group. Now think about the -OR group. Instead of having an H attached to the O, there is a C. This single carbon has a higher electronegativity than a single hydrogen. This means that the carbon is able to hold on to its electron longer than the hydrogen can. This makes the -OR group more stable than the -OH group if it were to receive the pair of electrons (if the -OH received the electrons, then we would just end up exactly where we started). While -OR will create a strong base when the bond is cleaved, the resulting carboxylic acid is not a strong acid. It is a rather weak one. Weaker than vinegar.
In real life, OH would be leaving too, but that would just mean going back on forth on the same rxn, so we're only focusing on the reaction of interest
at 2:44 you say "this would be step 1, we kind of have this addition of this OR group" but I think you mean "we kind of have this addition of this OH group". Most of us probably figured this out but just letting you know. Could you clarify the sodium ionic bonding please?
Base promoted ester hydrolysis? More like "Bro, a great explanatory video this is!" 👍
Thank you. Have been wanting someone to say in words the mechanism.
Took me a min to understand it😶
But true......
Hydrolysis reaction. Hydrolysis, hydrolysis reaction..
Loved this explanation! Thank you
its a different person teaching this video.... i can't learn from this new person... i need my khan academy guy to tell me this information.
Really....😕
I was curious about the chemistry of what’s going on while I’ve been wiping tobacco tar off the walls of a house with trisodium phosphate solutions. Pretty cool.
So H2O is used only to ionize NaOH?
Thank-you so much!, big help :)
In the second structure of the mechanism, could anyone explain why -OR would leave instead of -OH? If -OH is a bad leaving group (which is true), isn’t -OR in general an even worse leaving group?
Its because while -OH is a bad leaving group, -OR should be a better leaving group. As the electron from the charged oxygen goes back to the carbon to reform the double bond, the electrons on each one of the other oxygens have to make a choice as to which one will go to their respective oxygen and leave.
Think about -OHH. This is an excellent leaving group. Why? It is because when the electrons go to the -OHH group, it forms H2O which is a super stable molecule. Think about the electron negativities of oxygen, Hydrogen and carbon. While oxygen wins at 3.5, C comes in 2nd at 2.5 and H comes in third at 2.1. When an O has one H on it, the pull from the hydrogen is not enough. When there are two hydrogens, the pull is strong enough to make it an awesome leaving group.
Now think about the -OR group. Instead of having an H attached to the O, there is a C. This single carbon has a higher electronegativity than a single hydrogen. This means that the carbon is able to hold on to its electron longer than the hydrogen can. This makes the -OR group more stable than the -OH group if it were to receive the pair of electrons (if the -OH received the electrons, then we would just end up exactly where we started).
While -OR will create a strong base when the bond is cleaved, the resulting carboxylic acid is not a strong acid. It is a rather weak one. Weaker than vinegar.
In real life, OH would be leaving too, but that would just mean going back on forth on the same rxn, so we're only focusing on the reaction of interest
Excellent explanation! Thanks khan academy
Great video..........was really helpful !
at 2:44 you say "this would be step 1, we kind of have this addition of this OR group" but I think you mean "we kind of have this addition of this OH group". Most of us probably figured this out but just letting you know. Could you clarify the sodium ionic bonding please?
Can a weak base promote the hydrolysis?
Thank you!!
Can this be used in a vat to clean metals?
Sapon means soap in arabic
that's sabun ....same thing cause Muslims invented it .... :)
Mohamedingermany thnx for telling us:)
Sabon also means soap in Filipino
In Palestine we pronounce it as "sabuna", or I might have remembered that wrong. I'm heavily americanized
Almost the same with Malay.
Sabun (sa-bone) = soap
I didn't understand
isn't the ester compound known as triglyceride,not triglycerol
These are two valid names for it
pretty sure you got your R groups backwards at the end
Learned status: 1%
I think you should have written "triglyceride" instead of "Triglycerol"!
I believe the two words can be used interchangably.
Thank youuu
Um. What?
you sound similar to bruce banner haha😆😆
It's triglycerides not triglycerols.
triglycerol is an old valid name I think.
Triglycerol is 3 glycerol molecules condensed together.
Fateechar explanatiOn
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