When i was low on fuel i reconstruced the electrical engeneering wireing to absorb friction electronics gathering of power into the batteries Nd recycle the spent fuel aboard the ship
I'm in year 12 right now (UK) and the fact that I can understand this (even though it's beyond Alevel) shows just how good she is as a lecturer!! I wish I had teachers like her!
@@akshat_shukla00 why tf it sucks on the fact that it was taught in 11th? I am an indian too but we indians just try to drag this thing everywhere that our education system sucks even if its not even the context of ongoing discussion. I know its sucks but dragging it everywhere wouldnt help either.
In Ph3 bond angle is 90' as sp mixing is negligible because d orbitals can't be contracted because surrounding atom has less electrongativity so there are 3 p pure orbitals which are perpendicular to each other .
soap 7 hello Soap 7, could you explain, in case of nitrogen, which sigma bond will be counted either from 2s or 2pz, and lone pair comes from where? Thank in advance
@@mossammadu.c.sultana8548 well NH3 undergoes hybridization unlike it's other members of group 15. It is explained by drago's rule. And it has a lone pair because nitrogen has 5 valence electrons out of which the vacant p orbitals form hybrids with Hydrogen s orbital. The two paired electrons are lone pair.
Whats the difference between the bond angle of NH3 and PH3? Both N and P have lone pairs. Perhaps P having an unfilled 3d orbital does have an effect in the difference in bond angles.
In ph3 drago rule is operated which 3rd period and above periods of p blocks elements does not undergo hybridization when connected with less electronegative element like hydrogen!!
well i think the bond angle would be greater than 90 but near to it and only option it would fit would be angle less then 109 so i think that's why it was the correct answer
And so this lecture makes it clear as to why every STEM major needs multiple areas of math. Everyone knows physics and engineering has shit ton of math but so can chem and bio.
best explaination, you must have a happy class with exciting comphrehension. you saved my time and i will follow up on your videos as they are much effective in learning and comphrehension.. thank you so very much
When positive parts of wave have been used to form the bonding orbital, now where positive part is left to form anti bonding orbital Either we should speak positive and positive will make bonding and negative negative will form antibodies or we should speak either there will be bonding or there will be antibonding
This is amazing! Is there a continuation of this lecture or another lecture maybe, explaining poliatomic orbital theory, molecular term symbols, point groups maybe and their relation to degeneracy???? PLissss
4:44 listen to this statement this statement changed a big misconception of mine which was there with me for years, I suggest this highly if you are a jee aspirant
Well I wanted to learn about The Molecular orbital Diagram of N2 ²- Had a doubt wether your eating the pie trick will work here ? Or it is different ?.
in the formation of MOs, it looks like a chanced base whether it will be the bonding type or antibonding type than at the energy scale why it seems that both BMOs and ABMOs are being formed at the same time.
Yeah since it has pure orbitals. I think that can be explained by drago's rule which states that in group 14,15,16 the 2nd to last element doesn't undergo hybridization. So it combines with pure orbitals like PH3. It has 3 vacant p orbitals and H has 1 vacant orbitals of s. They form angles at perpendicular angles.
ca you explain please 1-The energy diagram of N2, O2 and F2 does not have any nonbonding electrons even if they contain lone pairs. From where does the energy transition come from? 2-What is meant by anti bonding orbital in case of H2 molecule when there is no electron in it? 3-Why two hydrogen electron wave function interfere both constructively and destructively simultaneously for the formation of bonding and anti-bonding molecular orbitals i.e they have phase difference of m lamda and m+1/2 lamda? please reply as soon as possible..............
(13:15) won't spin be the overriding factor as to whether a covalent bond forms ?? the spin magnetic moment between the two electons wanting to align the spins (up - down) will be way higher than the orbital magnetic moment around the nucleus or won't it ?? wish the professor would explain the reason
Shouldn't the answer to the clicker question be 'approximately 90 degrees' as the hybridisation of the central atom isn't considered in the hydrides of atoms in the nitrogen family below the second period according to 'Drago's Rule'?
One thing I don't understand and not found anywhere till now is how bonding and antibonding molecular orbitals can form simultaneously i e if we are linearly combining and atomic orbitals they can either combine constructively or destructively how both of them are happening together? I e why do we consider all the POSSIBLE COMBINATIONS only one of them can happen not both.
22:33 - why are the two e- in σ1s*, antibonding orbital, paired that is identical to the bonding orbital except the energy difference, shouldn't which be two singly occupied orbitals instead to be consistent with antibonding' ?
Thank you very much Catherine. I have one question. What about the non-bonding electrons according to molecular orbital theory? For example CO has 2 non-bonding electrons on carbon and 2 on oxygen. Can we predict these non-bonding electrons with the molecular orbital theory?
The electrons in my brain are not happy...in fact I don't believe electrons are happy anywhere, anyplace or anywhen. Basically two thirds of the class did not understand the metaphor of happier...or the reality of energy conservation (and I presume thermal enthalpy dissipation?) so what is the point of teaching by metaphor here? Once they get it wrong the lessons progresses by insisting on the "sweet spot" analogy idea rather than more degrees of freedom or more "space" to occupy or whatever it is that confers a lower energy level on the electrons - and introduces an up down concept that is yet to be explicit. These are notes as I go along. They aren't meant to be hyper-critical it's just that I've come to MIT online for an explanation when no-one has previously provided me one. Dirac (a Bristol lad with Asperger's?) has something to say I believe? Ok so now we are 24 minutes in and considering the bond order of a nonexistent He². It's dawned on me that the ² superscript has nothing to do with the square of the probability wave function, but rather is Chemistry notation not maths. Also we had a diagram of superposition where the difference of the energies has a negative value (this is not a square of probability? because that would be positive) and the whole plus or minus thing is totally confused in my head because the graph appears to have nothing to do with electrostatic charge. Jeeze this is one confusing subject. And Bond Order: why take half? It's not because "always there is a half" that's simply a way of remembering the definition. The whole BO concept is presented as gospel before it's defined... And then He² does exist but with a bond 40,000 times less strong than H² - discovered 1990s - so what does that mean? Given enough time and low enough temperatures all the He will end up as He²? Fate of the universe stuff? Presumably most He falls into stars before it cools enough to form He². I'm aware that Sussex UK discovered loads of complex organic molecules in deep space...
Hello, Can you please explain: I understood when you mentioned that when (Z is = or > 8) sigma orbital comes first, and when (z < 8) Pi orbitals come first. However, can you explain what you refer to as "Z" how do you find the value of it, where does this value come from?
Catherine Drennan you are literally my saviour! I wish my professor taught things with the same level of explanation and passion as you!
Thank you so much, Catherine. You've become one of the best chemistry lecturers I've ever witnessed. Great explanations!
it's almost impossible to not to understand her. Thanks, for such a great video!!!
Here Pi on t shirt is not from maths, it's chemistry
THE FIRST QUESTION WHERE THE ANGLE CAME OUT TO BE 109.5 HOWEVER THE COMPOUND IS DRAGO COMPOUND SO IT ANGLE QOULD BE 90 +_ 5 DEGREES
93
these courses are life saving
thank you MIT
When i was low on fuel i reconstruced the electrical engeneering wireing to absorb friction electronics gathering of power into the batteries Nd recycle the spent fuel aboard the ship
I'm in year 12 right now (UK) and the fact that I can understand this (even though it's beyond Alevel) shows just how good she is as a lecturer!! I wish I had teachers like her!
Hi
How are you!
Man, our education system sucks, in India these are taught to year 11.
@@akshat_shukla00 why tf it sucks on the fact that it was taught in 11th?
I am an indian too but we indians just try to drag this thing everywhere that our education system sucks even if its not even the context of ongoing discussion.
I know its sucks but dragging it everywhere wouldnt help either.
@@binodtharu8348 eh, I made that comment 8 months ago, don't get worked up
1:01:41 aí a prof realmente se empolgou, e com razão. Isso é paixão. admirável. Meus parabens.
ழுஜுவோஞமழாவுஸ ழுமுபஜு த ழழூஜா. ஐமுழஜேஜே
The lecture is really good and deeply understandable. Thank you Ma'am.
In Ph3 bond angle is 90' as sp mixing is negligible because d orbitals can't be contracted because surrounding atom has less electrongativity so there are 3 p pure orbitals which are perpendicular to each other .
The answer to PH3 should be about 90° because it is a Dragos Molecule; doesn't undergo hybridization and has a lone pair as well.
Yes absolutely is should be 93°
Exactly!! I was searching for this and was surprised that there is only one comment!!!
Exactly!!
actually in PH3 hybridisation is negligible because of drago's rule so the angle should be approximately 90 degrees
soap 7 hello Soap 7, could you explain, in case of nitrogen, which sigma bond will be counted either from 2s or 2pz, and lone pair comes from where? Thank in advance
@@mossammadu.c.sultana8548 well NH3 undergoes hybridization unlike it's other members of group 15. It is explained by drago's rule. And it has a lone pair because nitrogen has 5 valence electrons out of which the vacant p orbitals form hybrids with Hydrogen s orbital. The two paired electrons are lone pair.
Whats the difference between the bond angle of NH3 and PH3? Both N and P have lone pairs. Perhaps P having an unfilled 3d orbital does have an effect in the difference in bond angles.
Professor Catherine thank you for this awesome class. I understand alot now
Such a great teacher. Wish i got a teacher like u... Great explanation
Lucidly explained. Thankyou, Catherine!
I wish I were in the class all the above in MIT😶🔥🔥🔥🔥🔥
Thank you! I cannot believe it took me just this video to understand this theory.
Ma'am, you are great. Thank you MIT Opencourseware , thank you ma'am. THIS VIDEO IS LIFE SAVER ❤️💯💯
Doesn't PH3 have bond angle close to 90 degree as it has unhybridized pure p orbitals?
Yep
yes thats also what i thought same goes for SH2
Nope Tetrahedral have angle 109.4 and due to a lone pair in PH3 bondpairs come closer
Right. I was thinking the same.
Yes dragos rule
It's great to watch the lecture after studying the topic.
Really helpful...
Grateful I m
In ph3 drago rule is operated which 3rd period and above periods of p blocks elements does not undergo hybridization when connected with less electronegative element like hydrogen!!
Yeah and the *bond angles* should be ≈90° not
MY LIFE'S BEST EXPLANATION OF PI ORBITAL IN MOT!
I think the bond angles in ph3 should be 93 deegrees each ,as a consequence of Drago's rule.
well i think the bond angle would be greater than 90 but near to it and only option it would fit would be angle less then 109 so i think that's why it was the correct answer
God of inorganic vj sir...
this is really legit. first time I have ever understood this
Thank you, I did not understood this theory very well in class, and your explanation made total sense to me now
And so this lecture makes it clear as to why every STEM major needs multiple areas of math. Everyone knows physics and engineering has shit ton of math but so can chem and bio.
best explaination, you must have a happy class with exciting comphrehension. you saved my time and i will follow up on your videos as they are much effective
in learning and comphrehension.. thank you so very much
This is such an amazing lecture. Truly fabulous at what she does! Thank you.
It's what I wanted as a explanation..... 👍
She Rocks!!
When positive parts of wave have been used to form the bonding orbital, now where positive part is left to form anti bonding orbital
Either we should speak positive and positive will make bonding and negative negative will form antibodies or we should speak either there will be bonding or there will be antibonding
Its really helpful
It has helped me in grasping concepts of (LCOA)
I am very thankful to both MIT and madam who delivered this lecture
1:01:15 - This crazy molecule, O2, is what makes life on earth possible and yet it destroys everything it comes to contact with !
All the way from India...loved the class!
This is amazing! Is there a continuation of this lecture or another lecture maybe, explaining poliatomic orbital theory, molecular term symbols, point groups maybe and their relation to degeneracy???? PLissss
There is a playlist of these series, check em out :)
In the description
What a great lecture, thanks from Germany!
Please share some assignment links .
And the lectute was very good.
explains what an entire chapter of my textbook barely does
Thanks to MIT. Thanks to professor Catherine.
I would like to know more about wave functions
4:44 listen to this statement this statement changed a big misconception of mine which was there with me for years, I suggest this highly if you are a jee aspirant
When drawing a diatomic compound with different heteroatoms, electronegativity would indicate the energy levels in which the AOs lie.
professor thank you so much and for MIT also!
Can u please explain why sigma 2p orbital energy varies with atomic number,and how did u compare energy between sigma 2p and pi 2p
the second half is amazing
Thank you so much, Catherine
Best lecture of my life
Well I wanted to learn about The Molecular orbital Diagram of N2 ²-
Had a doubt wether your eating the pie trick will work here ? Or it is different ?.
It is fucking awesome that you need quantum mechanics to properly explain why hydrogen forms H2.
Thank you MIT , really helped me understand MO Theory basics
in the formation of MOs, it looks like a chanced base whether it will be the bonding type or antibonding type
than at the energy scale why it seems that both BMOs and ABMOs are being formed at the same time.
brilliantly explained, all of it
This is really helpful..... I was struggling with the concept of molecular orbitals....all of my doubts are clear now...thank you....
The Bond Angle of PH3 is around 90 degrees , the explanation in the video is wrong. PH3 doesn't go through sp3 hybridization like NH3.
yes i was searching for this
Yeah since it has pure orbitals. I think that can be explained by drago's rule which states that in group 14,15,16 the 2nd to last element doesn't undergo hybridization. So it combines with pure orbitals like PH3. It has 3 vacant p orbitals and H has 1 vacant orbitals of s. They form angles at perpendicular angles.
Trigonal pyramidal can have bond angles of 90°
She might not have gone into it since the next video is on hybridizing.
Hey friends you talk about 3 valency of PH3 but mam, asked question of 5 valency PH3
This video is amazing thank you so much Catherine ma'm......,.......
Why she didn't explained about the type of nodes in ABMO ? I thought there'll be more description about the nodes ( like their names etc )
ca you explain please
1-The energy diagram of N2, O2 and F2 does not have any nonbonding electrons even if they contain lone pairs. From where does the energy transition come from?
2-What is meant by anti bonding orbital in case of H2 molecule when there is no electron in it?
3-Why two hydrogen electron wave function interfere both constructively and destructively simultaneously for the formation of bonding and anti-bonding molecular orbitals i.e they have phase difference of m lamda and m+1/2 lamda?
please reply as soon as possible..............
zeeshan kashmiri Do you find the answer ?
Please reply if you get these answers
(13:15) won't spin be the overriding factor as to whether a covalent bond forms ?? the spin magnetic moment between the two electons wanting to align the spins (up - down) will be way higher than the orbital magnetic moment around the nucleus or won't it ?? wish the professor would explain the reason
Thanks alot madam thats enough for my first semester exam
Shouldn't the answer to the clicker question be 'approximately 90 degrees' as the hybridisation of the central atom isn't considered in the hydrides of atoms in the nitrogen family below the second period according to 'Drago's Rule'?
Thank you so much Catherine
Thank you for the refresher on MOT!
One thing I don't understand and not found anywhere till now is how bonding and antibonding molecular orbitals can form simultaneously i e if we are linearly combining and atomic orbitals they can either combine constructively or destructively how both of them are happening together? I e why do we consider all the POSSIBLE COMBINATIONS only one of them can happen not both.
Thank you! It was great to see this!
Why not dragos rule in the 1st question? The angle becomes 90° due to the large size of phosphorous in comparison to those tiny hydrogen atoms
🐥👈he says thanks for leveling the playing field ….. He supports your team ….These videos keep getting more and more and more useful…. 🤩 wow…
Thanks a lot prof!
You're the best
U know how to make students understand
How can two atoms combine constructively and destructively and the same ?
Probability factor
"A half, it's always a half."
It's stuck to my brain now 😂
Thank you so much this saved me
good stuff
22:33 - why are the two e- in σ1s*, antibonding orbital, paired that is identical to the bonding orbital except the energy difference, shouldn't which be two singly occupied orbitals instead to be consistent with antibonding' ?
Wow, a crystal clear lecture !!!
"not necessarily enough to power star-ship"
reference->Star Trek
cringe -> very much
How is it a reference? Simply because they have starships in star trek?!?
Thank you ma'am.. I love you for this.may God bless you.
Thank you very much Catherine. I have one question. What about the non-bonding electrons according to molecular orbital theory? For example CO has 2 non-bonding electrons on carbon and 2 on oxygen. Can we predict these non-bonding electrons with the molecular orbital theory?
Did you set up an MO diagram for CO?
@@joshcantrell8397 yes I did
Wait isn't the first one's answer slightly less than 90 degrees since phosphorus doesn't undergo hybridization in ph3
With reference to the clicker question , wouldn't the angle be 90 degrees because the p atom would remain unhybridized as per drago's rule?
Thanks Catherine.
What does it mean that the molecular bond axis is cylindrically symmetric?
Life saver, she is :)
What means @59:00? Why will biradical break a bond??
Thank you! very helpful
Very helpful lecture. Also the professor looks like actress who plays the dragon queen lady on Game of Thrones.
Isn't the PH3 is a drago's compound so its bond angle should be 90°
Thodi si variation aati hai approx 95° ka hota hai bond angle
93 degree aprox
much love
Mam, your lecture was awesome. Please let me know from where did you get the info regarding He 2 existence.
It is well known and studied in lab.
The electrons in my brain are not happy...in fact I don't believe electrons are happy anywhere, anyplace or anywhen. Basically two thirds of the class did not understand the metaphor of happier...or the reality of energy conservation (and I presume thermal enthalpy dissipation?) so what is the point of teaching by metaphor here?
Once they get it wrong the lessons progresses by insisting on the "sweet spot" analogy idea rather than more degrees of freedom or more "space" to occupy or whatever it is that confers a lower energy level on the electrons - and introduces an up down concept that is yet to be explicit.
These are notes as I go along. They aren't meant to be hyper-critical it's just that I've come to MIT online for an explanation when no-one has previously provided me one. Dirac (a Bristol lad with Asperger's?) has something to say I believe?
Ok so now we are 24 minutes in and considering the bond order of a nonexistent He². It's dawned on me that the ² superscript has nothing to do with the square of the probability wave function, but rather is Chemistry notation not maths. Also we had a diagram of superposition where the difference of the energies has a negative value (this is not a square of probability? because that would be positive) and the whole plus or minus thing is totally confused in my head because the graph appears to have nothing to do with electrostatic charge.
Jeeze this is one confusing subject.
And Bond Order: why take half? It's not because "always there is a half" that's simply a way of remembering the definition. The whole BO concept is presented as gospel before it's defined...
And then He² does exist but with a bond 40,000 times less strong than H² - discovered 1990s - so what does that mean? Given enough time and low enough temperatures all the He will end up as He²? Fate of the universe stuff? Presumably most He falls into stars before it cools enough to form He². I'm aware that Sussex UK discovered loads of complex organic molecules in deep space...
"not necessarily enough to power a starship" - Prof on Dilithium
Thnxs a lot ma'am for the wonderful lecture
Where can I get those t-shirts?! I want them!
thks a lot...very helping love from india
Hello,
Can you please explain: I understood when you mentioned that when (Z is = or > 8) sigma orbital comes first, and when (z < 8) Pi orbitals come first. However, can you explain what you refer to as "Z" how do you find the value of it, where does this value come from?
"Z" is the atomic number of an element
@@garymann3677 does that mean it only works for 7 elements out of all other elements?
HOLY SH*T I FINALLY UNDERSTOOD the + , - sign in M.O THANK YOU
Thank you very much.
Thanks a bunch no no no thank a billion 🙏.
It was wonderfully helpful.
helpful lessons