Wow really great video, especially the bit about shining the colored light thru it, never actually realized how the Copper actually absorbs the color we don’t see
Best question yet! (and beyond the IB). In reality the bonds formed are so weak that they are regarded as physical not chemical. The interaction is minor (though you would think the dative covalent bond would be strong). Short answer is I do not know!
Hey, Mr. Thornley, Just wondering a question: If the electrons in 3d orbit of lower energy receive energy to go up to the higher energy part of 3d, would they release their energy and fall back to the lower energy part of 3d? If so, would the complex [Cu(H2O)6]2+ appear orange at some time when it releases the energy?
The orange colour goes in all directions so appears super faint. Phosphorescence is the delayed release of light. Maybe if there is a slight delay and u had the right equipment you could measure the orange. OR the electron jumps down many small energy levels emmiting IR and we see no orange
Hi Mr. Thornely. Quick question, I understand how if there is minimal d-d splitting the ion could be colourless and white but how would black arise? since its not absorbing any of the visible light?
he gave an example of octahedral complex...but in tetrahedral complex, the reverse of it happens..that is..3 orbitals(t2g) go up. You can read "crystal field theory" to understand it in a better way :)
I have a question about valence electrons. In organic chemistry it's pretty straight forward that each atom tries to fill 8 electrons per atom to remain stable. But everything seems to fall apart in the transition metals. With the examples of Cu+1 and Cu+2, the carbon has 3d10 or 3d9 in its d orbital. So then how can you add 6 ligands to the copper? What happened to the octet rule? If you throw on 6 ligands, what just happened to the d10 or d9 electrons that were previously there?
+ThisIsMyUsernameYesItIsVeryLongYouDidntThinkThatItWasEvenPossibleWaitWhyAreYouEvenReadingThisSTOPNOW A quick check on Wikipedia says it is to do with bonding, antibonding and back bonding!
But then what happens to the electron that went into the higher energy orbital, does it stay up there? Where does that absorbed energy go so that the color can be absorbed again? Otherwise wouldn't the solution become increasingly colorless?
The excited electron in the higher energy level will only remain at that level for a very short period of time. To achieve stability, the excited electron will undergo transition back into the lower energy level, releasing a photon where the energy E of it is defined as E=hf, where h is the Planck constant and F being the frequency of the electromagnetic radiation it was exposed to.
The energy of the photon corresponds to the crystal field splitting energy, which in simple terms, mean the "energy gap" between the d orbitals that were split by the introduction of ligands
If a complex ion reflect certain colours, which is the combination of colours it can't absorb, and emit the same colours it has absorbed (the energy gap is the same so it must absorb and emit same frequencies), won't it actually looks like all colours combined? Maybe black?
Hey Mr. Thornley, since the d-orbitals only split if there are ligands attached and if there is light passed through it, will the transition metal ion solution have a colour if a room is pitch-black? i.e. if you placed it in a colorimeter, would it give any readings?
no light = no absorbtion! if I reinterpret you question - the d-orbitals must split a little bit even without ligands (due to heat/random quantum fluctuations etc) so a small split would absorb small energy = far far infra red maybe
Hi Mr. Thornley, My ib teacher recommended you to me and I love your videos! Just a question, how do we know which colour is absorbed? I know that the colour emitted is the opposite colour on the colour wheel of what was absorbed, but how do you find which is absorbed in the first place?
+Josh Hayden Well it is the opposite of the colour you see! I would remember that copper sulphate (aq) absorbs orange to show blue (an IB favorite). The real answer must lie in some complex calculation involving metal ion type, charge, ligands, arrangement and temperature.
@@mewying5184 currently finishing my MSc in biochemistry and molecular biology, studying the use of boron-containing compounds to inhibit a certain enzyme! I will be moving away from chemistry to start dental school in the fall, however, my love for chemistry that started in IB will always remain!
![13.2 What are the Reasons for the Different Colours of Complexes? [HL IB Chemistry]](http://i.ytimg.com/vi/4BzPDVRo8n0/mqdefault.jpg)
![13.2 What are the Reasons for the Different Colours of Complexes? [HL IB Chemistry]](/img/tr.png)
![S3.1.10 Why are Complexes Coloured? [HL IB Chemistry]](http://i.ytimg.com/vi/Kq_tKki1syE/mqdefault.jpg)
So clear!!! I love it! Thank you so much. Sincerely, a stressed and fried IB student trying to learn a whole isn't in one night
I really wish I had found your videos sooner, but they are really helpful!
Wow really great video, especially the bit about shining the colored light thru it, never actually realized how the Copper actually absorbs the color we don’t see
what z mindblowing video....everything crystal clear
Wow, best explanation ever!
Best question yet! (and beyond the IB).
In reality the bonds formed are so weak that they are regarded as physical not chemical. The interaction is minor (though you would think the dative covalent bond would be strong).
Short answer is I do not know!
Great work man 👍
This is just a general rule since concentrations and types of solvent can also change the colour. But you are correct!
Thank you for your nice video. I have question, how the molecular orbital diagram [Cu(H2O)6]+ looks like?
Thank you so mucn
Hey, Mr. Thornley,
Just wondering a question:
If the electrons in 3d orbit of lower energy receive energy to go up to the higher energy part of 3d, would they release their energy and fall back to the lower energy part of 3d? If so, would the complex [Cu(H2O)6]2+ appear orange at some time when it releases the energy?
The orange colour goes in all directions so appears super faint. Phosphorescence is the delayed release of light. Maybe if there is a slight delay and u had the right equipment you could measure the orange.
OR
the electron jumps down many small energy levels emmiting IR and we see no orange
@@ibchemvids Thank you so much Mr Thornley
Superb
Hi Mr. Thornely.
Quick question, I understand how if there is minimal d-d splitting the ion could be colourless and white but how would black arise? since its not absorbing any of the visible light?
Hey Richard, what program do you use for all your diagrams? :D
activstudio and an activboard
Do all transition metals split in the same way (3 lower, 2 higher)?
It's been 6 years , but no they don't tetrahedral ions like CuCl4^2+ split 2 lower 3 higher
This is absolutely brilliant!!!
So both indigo and violet give yellow and vice versa?
Hello Mr. Thornley!
Why is it that only two orbitals move to a higher energy level? And why do they move to a higher energy level??
he gave an example of octahedral complex...but in tetrahedral complex, the reverse of it happens..that is..3 orbitals(t2g) go up. You can read "crystal field theory" to understand it in a better way :)
Thanks! :)
+Deeksha Tewari you're welcome :)
I have a question about valence electrons. In organic chemistry it's pretty straight forward that each atom tries to fill 8 electrons per atom to remain stable. But everything seems to fall apart in the transition metals. With the examples of Cu+1 and Cu+2, the carbon has 3d10 or 3d9 in its d orbital. So then how can you add 6 ligands to the copper? What happened to the octet rule? If you throw on 6 ligands, what just happened to the d10 or d9 electrons that were previously there?
+ThisIsMyUsernameYesItIsVeryLongYouDidntThinkThatItWasEvenPossibleWaitWhyAreYouEvenReadingThisSTOPNOW A quick check on Wikipedia says it is to do with bonding, antibonding and back bonding!
But then what happens to the electron that went into the higher energy orbital, does it stay up there? Where does that absorbed energy go so that the color can be absorbed again? Otherwise wouldn't the solution become increasingly colorless?
The excited electron in the higher energy level will only remain at that level for a very short period of time. To achieve stability, the excited electron will undergo transition back into the lower energy level, releasing a photon where the energy E of it is defined as E=hf, where h is the Planck constant and F being the frequency of the electromagnetic radiation it was exposed to.
The energy of the photon corresponds to the crystal field splitting energy, which in simple terms, mean the "energy gap" between the d orbitals that were split by the introduction of ligands
If a complex ion reflect certain colours, which is the combination of colours it can't absorb, and emit the same colours it has absorbed (the energy gap is the same so it must absorb and emit same frequencies), won't it actually looks like all colours combined? Maybe black?
Thank you sir!
Why is Cu H2O complex a 3 to 2 split?
Not sure - beyond the IB.
i was just talking to my friend about this ha, awesome :D
How do we know how the d-orbitals split? (a 3, 2 split was mentioned in this?)
just learn 3:2 split - no way to work it out really.
Hi sir, why is "6" water molecules are added to the Cu2+ ??
6 water molecules can fit. Bigger ions, such as Cl-, can only fit 4 around. There are other considerations too though.
This is great.
Fantastic video, thank you!!
Hey Mr. Thornley, since the d-orbitals only split if there are ligands attached and if there is light passed through it, will the transition metal ion solution have a colour if a room is pitch-black? i.e. if you placed it in a colorimeter, would it give any readings?
no light = no absorbtion!
if I reinterpret you question - the d-orbitals must split a little bit even without ligands (due to heat/random quantum fluctuations etc) so a small split would absorb small energy = far far infra red
maybe
Hi Mr. Thornley,
My ib teacher recommended you to me and I love your videos!
Just a question, how do we know which colour is absorbed? I know that the colour emitted is the opposite colour on the colour wheel of what was absorbed, but how do you find which is absorbed in the first place?
+Josh Hayden Well it is the opposite of the colour you see! I would remember that copper sulphate (aq) absorbs orange to show blue (an IB favorite). The real answer must lie in some complex calculation involving metal ion type, charge, ligands, arrangement and temperature.
+Richard Thornley Awesome, thank you so much!
@@joshhayden1706 where are u brocel theses days?
@@mewying5184 currently finishing my MSc in biochemistry and molecular biology, studying the use of boron-containing compounds to inhibit a certain enzyme! I will be moving away from chemistry to start dental school in the fall, however, my love for chemistry that started in IB will always remain!
@@joshhayden1706 wish u goodluck my bro
fuckin brilliant
Thanks
thx Hoss.
Really helped ..Cheers
ur genius
Sir Richard Thornley, OBE
Hi Mr Quilty!!
nice
In IB - yes
Excellent explanation with only essential points but too fast
The vids are review - and don't be afraid to pause and rewind!
fucking brilliant !!!!!
nice