Orbitals, the Basics: Atomic Orbital Tutorial - probability, shapes, energy |Crash Chemistry Academy
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- เผยแพร่เมื่อ 31 ก.ค. 2011
- A crash course tutorial on atomic orbitals, quantum numbers and electron configurations + practice problems explained.
CC Academy videos are easy 101 crash course tutorials for step by step Chemistry help on your chemistry homework, problems, and experiments.
-Stoichiometry Tutorial, step by step
-Types of Chemical Reactions: How to classify five basic reaction types
-Solution Stoichiometry
-Orbitals the Basics: Atomic Orbitals Tutorial
-Hybrid Orbitals Explained
-Polar Molecules Tutorial: How to determine polarity in a molecule
-Metallic Bonding and Metallic Properties Explained
-Covalent Bonding Tutorial
-Ionic Bonds, Ionic Compounds: What is an ionic bond and how do ionic compounds form
-Electronegativity and bond character (bond type): non-polar covalent, polar, ionic
-Metric Unit Prefix Conversions: How to Convert Metric System Prefixes
-Metric unit conversions shortcut: fast, easy how-to with examples
-Mole Conversions Tutorial: how to convert mole - mass, mole - particle, mass - particle problems
-Frequency, Wavelength, and the Speed of Light
-The Bohr Model of the Atom and Atomic Emission Spectra
-What is Heat: A brief introduction at the particle level
-Rutherford's Gold Foil Experiment
-Unit Conversion Using Dimensional Analysis Tutorial
-What is Fire: Combustion Reaction Tutorial
-Quantum Numbers Tutorial
-Electron Configurations Tutorial and How to Derive Electron Configurations from the Periodic Table
-Concentration and Molarity Explained
-Heating Curves Tutorial
-Naming Ionic Compounds
-Limiting Reactant Tutorial
-PV=nRT The Ideal Gas Law: What is it, What is R, Four practice problems solved including molar mass
-Gas density and PV=nRT, the ideal gas law
-Surface Tension - What is it, how does it form, what properties does it impart
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-More on Atomic Orbitals | Wikipedia-
"An atomic orbital is a mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom.[1] This function can be used to calculate the probability of finding any electron of an atom in any specific region around the atom's nucleus. The term, atomic orbital, may also refer to the physical region or space where the electron can be calculated to be present, as defined by the particular mathematical form of the orbital.[2]
Each orbital in an atom is characterized by a unique set of values of the three quantum numbers n, ℓ, and m, which respectively correspond to the electron's energy, angular momentum, and an angular momentum vector component (the magnetic quantum number). Any orbital can be occupied by a maximum of two electrons, each with its own spin quantum number s. The simple names s orbital, p orbital, d orbital and f orbital refer to orbitals with angular momentum quantum number ℓ = 0, 1, 2 and 3 respectively. These names, together with the value of n, are used to describe the electron configurations of atoms. They are derived from the description by early spectroscopists of certain series of alkali metal spectroscopic lines as sharp, principal, diffuse, and fundamental. ...
Atomic orbitals are the basic building blocks of the atomic orbital model (alternatively known as the electron cloud or wave mechanics model), a modern framework for visualizing the submicroscopic behavior of electrons in matter. In this model the electron cloud of a multi-electron atom may be seen as being built up (in approximation) in an electron configuration that is a product of simpler hydrogen-like atomic orbitals. The repeating periodicity of the blocks of 2, 6, 10, and 14 elements within sections of the periodic table arises naturally from the total number of electrons that occupy a complete set of s, p, d and f atomic orbitals, respectively, although for higher values of the quantum number n, particularly when the atom in question bears a positive charge, the energies of certain sub-shells become very similar and so the order in which they are said to be populated by electrons (e.g. Cr = [Ar]4s13d5 and Cr2+ = [Ar]3d4) can only be rationalized somewhat arbitrarily."
Wikipedia contributors. "Atomic orbital." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 17 May. 2016. Web. 27 May. 2016.
This is exactly what a chemistry lesson should be like. Expensive software, devices, or fancy animations are not important. At the end of the day, how simple and easy-to-understand a lesson is are the determining factors of the lesson's quality, and the creator of this lesson did a great job with that.
Is this quantum model of atom which sir has explained
@@prmomaths757 Yes. Introduced the idea of a probability density function.
At least your country has expensive equipment. Our country only have bulky books so we have to rely on TH-cam
Please let you suppose that animated lessons are for the sake of simplicity, because animated images are likely to be copied in a mind and so be easy to memorise and visualize, thank you so much
Although learning with virtual reality does sound kind of cool too 😅😂
That guy explained in less than 15 mins what my chemistry prof was trying to do for an entire lecture!
We must have the same professor lol
Wait is it professor Deen?
@@pullingthestrings5233 no mine was Professor Reddy
@@crystalmckinney3151 guess most professors are garbage on these courses.
We all are here because of the same reason😂😂
This video is a miracle for visual learners. Thank You!
Hi and thanks. While I should perhaps not get overly involved with your comment, as a teacher I have to speak up. Academics with no classroom experience and poor experimental design (if any), and the teachers who (mis)interpret their work, did and do the world a great disservice by introducing the concept of assigning different learning modalities according to sense (visual learner, tactile learner, etc.). I do not deny that people are often more comfortable with one modality versus another, or prefer one modality over another, but to be told by their teachers that they have one dominant learning modality is a sad misunderstanding of cognitive development, the learning process, psychology, and the strong influence that teachers have with their students. We need to be telling students that all learning modalities are important (they are), and that even though they may prefer one over another, or have been TOLD (by teachers!) that they learn better in one modality over another, the fact is we are telling this to people with enormously plastic brains, and what they need to understand is that they can LEARN to improve their learning in other modalities, and should in fact work at doing so, so that when their brains develop into adult brains, they can be adults that have a much greater capacity to learn in all modalities, which is so important in our very complex world. If you can learn in all modalities, then you can think in all modalities, and then you can make much deeper connections between all sorts of topics, and that makes you a far better thinker. And guess what? Adults have plastic brains too. They can learn to learn in all modalities. It is worth the effort!!!
Hope I didn't get too high on the soapbox! Thanks for "listening."
@@CrashChemistryAcademy I really appreciate this comment. As an older student, I can feel my physiology's resistance to thinking in these unfamiliar ways which is both alarming and invigorating. In running into these resistances, I get an experiential sense of broadening my mental horizons. It's a profoundly humbling experience and I appreciate your dedication to encouraging others to walk the path. I need all the encouragement I can get because it is so much easier to not try. Cheers, sir.
@@skinblanketed As a (somewhat) older learner myself, I know how fun it is to understand something you were struggling with. I'm right with you.
@@CrashChemistryAcademy you're great soul sir I HOPE UR DOING VERY WELL :)
@@alekku1782 😊
Wow out of so many other videos about orbitals, yours was the most clearest to me! I don't know if its just because I'm a visual learner, but whatever it is, your explanation is the clearest! Keep up the great work :)
ikr... I missed the class in school.... and I was so blank. god... this helped me a lot. at least I will now understand what's going on.
it was the clearest and it was slow and good visual graphics too.
Swati Ravishyam ikr. Crash Course and Khan Academy, despite how good they usually are, weren’t able to explain this as well.
@@lopkobor6916 exactly
This video along with couple of videos cleared up entirely. I began wondering and confusing myslef. I want able to imagine. Because anything to make sense u need to imagine it. And this video helped me get that .
I was having a hard time trying to visualize how orbitals overlap each other with different shapes and energy levels but this vid made it as clear as glass thankkk u genius
Thanks a lot for this!
It's worth it to clarify that, even though the whole “s for sphere and p for polar” thing is good for remembering as a mnemonic, for example, that's NOT actually what the letters stand for. The shell or orbital s stands for *sharp*, p stands for *principal*, d stands for *diffuse*, and f stands for *fundamental*. And the reason early spectroscopists gave them those letters is the way the “spectral lines” produced from spectroscopy looked like in each case; s's lines were “sharp”, p's lines were the strongest (“principal”), d's lines were “diffuse” (scattered or perhaps fuzzy in contrast with s's sharpness), and f's lines’ frequency ratios were similar to that of Hydrogen's so seemed to them...“fundamental”. This may not help as much as the mnemonics for early students, but it will certainly help if a student likes chemistry or chooses a career in it; you don't want to sound misinformed or ignorant of those facts when talking to other chemists.
dude that is pretty cool
What about g, h, and i?
The quantum number 'spin' is why each orbital lobe when filled, only has two electrons, one spin up, the other spin down. It is absolutely forbidden for an atom to contain two electrons with same quantum numbers, hence spin up or spin down, though electrons do not appear to spin. Quantum stuff blew my mind.
to maintain the stability ie energy they spin in apposite directions
RokWisdawn That's very interesting, I've always wondered why they were given those letters.
The more complexly shaped the orbital (say d vs s), the more energy required (angular momentum) for an electron to remain in that area. It takes more energy for an electron to be in a d shape than in an s shape, thus 3d electrons have slightly higher energy than 4s.
May we speak somehow?
@@jazzyfizzlemorrison8233 Feel free to email me in the address provided in the "About" section on my channel homepage.
@@CrashChemistryAcademy I went there but no email. If you don't mind could I ask of it from you here in the public thread? If not we will find another compromise
@@jazzyfizzlemorrison8233 jaw1627@gmail.com
That's not true. The energy depends only on the principal quantum number n, your 3 or 4 in this case, as long as you have a single electron and you use non-relativistic quantum mechanics. The splitting of the energy levels is mostly due to the interaction of several electrons with each other, and there are also small corrections due to relativistic effects and the magnetic field of the nucleus.
This is honestly one of the best explanations I’ve ever seen for chemistry, those visuals really work wonders
I agree !!
I was confused on orbitals for about a year and a half. My Honors Chemistry class didn't go into depth about them, and now that I'm in AP, we're expected to know them. Thank you for this video. I finally have an inkling of what they are.
This is the best explanation I've found. It's a very simple concept when addressed properly. I don't know why no one else thought to clearly match the shape to the letter and draw it on an axes to clearly give us a picture.
Those who explain it the best understand it the best. I will be flicking through your videos when I have grasped this :)
Thank you SO much!
Dude, you win! I've been trying to get a handle on this whole electron orbital setup (just for my own entertainment, cuz I'm a nerd and I'm into these things) and no other videos (even the really popular ones, like Bozeman science and Crash Course) explained it as well as you. Thanks!
I love visual explaination because i can use my imagination rather than knowledge
you mean rather than text
@@carlamariedelcarmen5944 ... its a 3 year old comment
@@GabrielGames100 5 year
@@AbsoluteArtist 6 years
27 yrs
This helped a lot! I'm currently taking an online course in Chemistry and their explanations are very vague, I'm glad I found this :) Thank you!
Thank you! This was so helpful for my Chemistry exam~ I looked every where and this really helped me understand orbitals!
this was extremely helpful! the visual descriptions were on point! thank youuuuu!!!
This was so much more helpful than the crash course. This gave me all the information I needed without giving me so much extra detail that I got confused.
THANK YOU SOOOOO MUCH for making this tutorial. I was stuck for a week on this topic of orbitals until my friend recommended this video to my group. It is so clear cut and manageable in terms of understanding. Thank you so so much. :DD
❤
8 years ago. I wonder where this bright mind is now 😎
I find this much better than Khan Academy! Excellent explanation and presentation.
Omer Khan plse don't compare. all teacher r giving their best only for us
one of the best explanations of orbital structures that i have gone through .. keep up the good work!
Wow, very well very well explained..best video I have seen so far explaining this, especially the orbitals overlapping presentation was what I was looking for. Good job, earned a sub mate, keep doing these things
At last, after A Level Chemistry and a degree in Geology, a clear explanation, really appreciate it, could have done with this 30 years ago.
awesome... i am glad glad i found this just in time since i am taking my as level exams soon. Thanks a lots , keep making more videos , you really are a great teacher why ? simply because you teach with no ambiguity, leaving us students with no questions but understanding.
Thank You!!! spent almost two hours flipping from my orgo textbook to my chemistry textbook and other youtube videos and this video is the only one that made sense to me. Awesome!!
FINALLY. Ive been looking for an actual description of an orbital itself and this is the only place that doesent just describe the quantum numbers, THANK YOU
I am glad to realize that my intelligence was not the reason why I could not understand this. Thank you very much for giving me faith in the fact that teaching can be good.
OMG OMG!! Ive been trying to understand the image of electron configuration and orbitals in my head but I couldn't because my professor wasn't able to help me nor any of the tutors I hired. After looking through numerous videos I finally understand orbitals. THANK YOU SOOOO MUCH!!!
Panagiotis Tsampas the same in my case.
This was amazingly easy to understand than most videos out there explaining orbitals. Thanks a lot!!
I cannot believe that this video is 9 years old but explains this in the best way possible, i really needed a visual representation and here i have it. Broken down so well thank you.
My teacher is really good, but you sir are in the next level! i love how you remind us of fundamental things over and over. keep up the good work!
dude i have taken college chemistry 1 and 2 and organic 1 and am now in organic 2 and i've struggled with understanding orbitals the whole time. I'm just now actually understanding the concept thanks to your video. Awesome job at explaining while keeping in mind that people watching this probably reeeaaaally just want to be explained in detail but without confusing words and other harder concepts thrown in.
The first and only explanation of orbitals that really made sense to me. Thanks very much!
Thank you so much for the video! I've been looking through a lot of articles and other content explaining this and related things, but your video was the turning point where I actually understood it. I really appreciate it!
You're welcome, thanks for watching!
Better explanation than khan academy
So much better! No hate on Khan Academy, I love em and watch their videos, but I was really confused when i watched the orbital video by them.
Myfavsandlikes I hate khan academy. Tyler Dewitt is the best chemistry you tuber and the only one who knows how to explain topics, unlike sal who loves to make topics sound as over-detailed and complicated as possible.
Actually yeah
So does Bohr technique work or should I choose a specific style for highschool?
@@justabarbiegirl The bohr model would only work for the hydrogen atom l so i would say keep it for finding electrons in the hydrogen atom
I've been trying to understand this topic for over 2 years. (I actually learned it 2 years ago, didn't understand it, and now have to learn it again) and I FINALLY UNDERSTAND. Thanks for being everything that my chemistry teacher should have been!!!!!
I was stuck on this in my textbook for a week, rereading it over and over. Thank you for clearing things up 😄
After searching and watching lot of videos on this topic for two days I found this simple & easy to understand video.Countless praises,salutes , appreciations and best regards for all the presenters of this video.
Best explanation thus far. Thank you!
Was so great,particularly about the visual representation . All I needed was an imagery of things snd this video perfectly meets what I need. Please do make such a helpful video for band gaps
Yes. The thing I needed was imagination. Simply telling that electrons move in orbitals and stuff wont reach the mind. Because u cant imagine that. This video helped me too.
This is the best video I have seen in regards to orbitals. Cheers buddy.
it's been 5 years i had been trying to understand orbitals.. finally because of you i got it clearly.. thank you
Thank you kind sir. You just saved the lives of countless chemistry students out there.
Great video! Helped me alot.
This was absolutely amazing!!! Been trying to learn this for the past week and your video finally made it click! Legend!
Dude you absolutely nailed that! This is the best video(i have watched tons of quantum numbers vids)on this matter!
Bless you...
You just saved my life
I hope this question makes sense, but for the sake of pursuing higher learning would someone care to try and explain why there is a higher probability of finding an electron within _those_ specific shapes? Does it have to do with the way electrons repel each other? Even if someone could link me to an article or something I would be very appreciative!
The behavior of electrons in an atom is described mathematically by the Schrodinger Equation (1926) which is called the quantum mechanical model, and which is still used for the basis of quantum mechanics today with some modifications. The equation has four variables that describe electron behavior, and the values allowed for those variables are called quantum numbers. When plugging in the allowed quantum numbers, the orbitals emerge. The probability aspect comes from the Schrodinger Equation defining the electron as a wave as the basis for the math, and the wave came from Louis de Broglie describing the basis for the quantization of electrons as a wave phenomenon (1924) which was interpreted by Max Born (1924) to be referring to the electron's probability of existing in any particular location. In Schrodinger's equation, the letter psi represents the electron wave, and psi^2 represents the probability of where the electron might be at a given moment within an orbital, but the entire orbital can only be represented as a space in which there is a certain probability of finding an electron, the 90% used in the video. The "certain probability" is necessary, because at 100% probability, the orbital balloons to take up the entire universe: there is a 100% probability of finding the electron somewhere in the universe. If the probability is shrunk down to 90%, then the math is able to describe a space, the orbitals, that are reasonably small enough to define the size of an atom. You may want to view my video about de Broglie's wave interpretation here: th-cam.com/video/oLd-6UytkIU/w-d-xo.html.
@@CrashChemistryAcademy That was such an interesting and complete response, thank you so much! I have never heard the "100% probability" explained like that before. I will watch the video you linked and I truly appreciate the thoroughness of your reply!
@@scisarah3770 You're welcome! This is fun stuff!
@@AhmedAli-mn5ht Yes, any neutral atom has the same number of protons and electrons. If the number of electrons was different (an ion) its properties would be very different than the neutral atom.
To Aptua: I think the same way! If you look at the orbitals as described in this very good video, it does make you wonder why the electrons "choose" those configurations in particular. And yes - the math points to those shapes. But again, why? There are several things to consider. The electrons, being all negatively (and equally) charged, do repel each other. But at the same time, they're attracted to the protons in the nucleus. Also, there's the strong nuclear force to contend with. I don't have the math for any of this, understand, I just try to grasp things conceptually, forming ideas and pictures in my head. Notice one key thing, though: the shapes of the (90% probability!) orbitals are a bit like flattened tear drops. The largest area is farther away from the nucleus - and from the other electron. So, in a sense, you could picture (very crudely, of course) the idea that the electrons, though attracted to the nucleus, must avoid getting too close to each other. The 'balance' if you will, is a sort of compromise between forces. Again, that's really crude, but a workable mental picture. We certainly progressed a great deal over the old models! At first, we thought (or rather, assumed) that electrons would orbit the nucleus like planets orbit the sun. Then we developed the "cloud" model, where they were just smeared out around the nucleus in no particular order. Now, we have a much better idea (and handy computer visuals) of the actual shapes. I hope this helps some, without being too crude or off-kilter. tavi.
I have watched so many and your explanation is by far the best one! thanks so much!
great vid! i was really struggning with how they "add up" and now i have atleast a pretty good idea. thanks so much
I love the way of your presentation and looking forward to see more of this topics in the near future. Chemistry is my favourite subject and your explanation tremendously inspired me. I really appreciate your video clip and enjoyed learning from it. Thank you very much for making this video and for your generous heart of sharing your invaluable knowledge of Chemistry concepts.
This the first video that I have found that actually explains all aspects of this topic, +1 and a new subscriber.
What an awesome video... I thought I was never going to fully understand this concept. Thanks a ton!
what a treat! great video. effortless learning!
This actually saved me. I was in tears because I didn't understand anything from the material my school gave me, and this helped me understand a lot. Thank you!
school is so f kin shit. I hate school
@@zekekace6882 but u shld enjoy schl life
@@fawndawn6159 nope
@@abdurrahmanlabib916 u r gonna miss it then
Honestly, this was such a good explanation.
Just amazing !!
Your visualization is fantastic !
This is by far the best explanation I have seen so far!
You are fantastic and i wish i had a professor like you. Your videos may be saving me from failing my chem class in which I have the worst professor on earth. He complicated every single concept while you make it sound so easy. You da bomb.com
Extremely interesting video on orbitals .
it is so glad that i found this video, best of explanation i ever had about quantum numbers
Thank you for this video! I'm getting back into Chemistry after 10 years, to further my career in the medical field. and quantum mechanical model was something I don't think I ever quite understood. I've watched a few videos, including Crash Course (I love the series. It's entertaining, but their orbital video didn't help me much). Your video broke it down and clarified the points I wasn't understanding. Thank you so much, and we'll done!
wow !! I totally understand this. Thank you !!!!
I feel like I have a better understanding of orbitals after watching your video! Thank you so much! ^_^
This is exactly all I needed...thank you 🙏🏽 for finally connecting the dots
after watching so many videos, i finally found one with amazingly understandable explanation. Thank you sir!
very well explained, thanks a lot
Finally satisfied , thanks so much....🙂🙂🙂
This stumble was Lucky.
Thank you so much! I’ve watched the other videos and they weren’t as clear as this one!
believe me this is coming from my heart this video was the best
so on point, the amount of clarity i gained through this cannot be explained in words
Thanks and good point-- my electron configurations vid goes into that.
Thank you so much for the video , I finally got to understand this. But what is the relation between the wave function psi and the different orbitals ?
One of the best explanations out there, understanding that these shapes are areas where there's high probability for electrons to be is exactly the part I was missing, just changing "orbitals" to "areas" or some other word would have made it much less confusing, but I get the historical reasons (bohr model) thanks for the video!
고맙습니다! 오랫동안 완벽히 이해되지 않았던 부분인데 이 영상을 보고 이해되었어요:)
천만에요! 유용하셨다니 다행입니다. 시청 해주셔서 감사합니다.
I drew them on Macromedia Freehand, which unfortunately is no longer commercially available. Adobe killed it, but their Illustrator is similar.
this video is awesome!!!! thank you
this video is gold, thank you so much for going in depth & explaining!
THANK YOU!! This topic has literally not made sense to me for 5 years, and you made it click in this video.
thanks for making this video it really helped in understanding ORITALS
Haha!! Guess who's acing his quiz tomorrow!? This was very helpful!
did you ace the quiz? :>>>
This might be the best video explaining orbitals on TH-cam.
Amazingly useful and so clear! Thank you so much!
Great video! You sound like Steven Segal by the way :)
I've been researching my family tree and have discovered that I actually am Steven Segal. It was quite a shock, but the wealth and fame have cushioned the blow.
this is so much better than waking up to study.
Ikr, going to sleep studying is better than waking up studying hahaehaahoohoo
Best explanation ive found online ! Keep it up
This explained to me in 12 minutes what Wikipedia and S-cool couldn't do clearly in 2 hours. Great vid!
i learned a lot ........tq for posting
Much better than Hank Green!
haha yup
totally agree although he's been really good for everything else so far and I'm up to episode 25
I laughed so hard when I saw your comment omg
Nice to know I'm not the only one who didnt get Hank's explanation hahah
HAHA! You're so right! The only reason I watched Crash Course Chemistry is because his personality Is so addictive! >.< He doesn't explain it that great, but it's so fun to watch! X'D
Haha, I came here just because I didn't get the orbitals analogy about music.
There is no video that is better than this on this topic. Amazing. Hats off.
this is the best explanation of orbitals that I have found on the internet.
amazing
bane goade
diagrams were useful
Such a great video! I wish all science vids were as clear as thinks. Thank you!
Thank you!!! I've watched 3 videos already on orbitals and was completely lost. Breaking it down visually was super helpful.
I’m glad it helped!
Why are the axis mixed up? like isn't the vertical axis called "Y", and the slanted axis called "Z".
Thanks for the great video btw!
I know it's 5 years later, but I noticed the same thing
@@kriyaramjuttan9499 actually in 2d we have x and y lengths. And if we add it height to these lengths it will be in 3d. So if you think that you are looking from the positive side of z axis, you can see the x and y axises. I think that is the point. :)
Is it possibly easy to explain why dumb-bell orbitals have such an unusual shape? Same for doughnut shape, please. What is the root cause which influences the shape of orbitals?
Good question I would like to know as well.
its a solution to a 3-d equation - that shape solves the (eigen-) equation
Rick Deckard That's obvious, it doesn't need mentioning. What are the principal influences, in short, on which these equations are based? What two or three influences are in balance with each other?
HitAndMissLab thats obvious, if you know what an eigenfunction and probability amplitude are...lol....why are you even mentioning it?
Rick Deckard Its not obvious, to me at least. I am not an expert, but you are.
Awesome video, loved the visuals and the definitions
This really helped me understand electron orbital a lot more clearly. Thank you.
I still don't understand. But science no one else is complaining I'll go cry myself to sleep
Since*
What is it exactly that you don't understand?
Andres fierro you and me both
Bro
I don’t know about your basic knowledge but this can be easily understood if you have some knowledge already about chemistry.
I mean am an a level student ,
I can’t solve questions of higher level unless I understand my own level
Maybe you should take help of someone who has the basic knowledge.
He can understand and make you understand this
Heisenberg? The one who knocks?
No-- the one who cooks.
The one from whom the name was taken.
Then name Heisenberg is already taken. Would you like Heisebergknocks67?
after checking 100's of youtube videos, i must say you are indeed the master of explaining things. your knowledge is concise and easy to understand and thorough.
only video i have seen that actually shows and explains how each orbital overlaps and is arranged around the nucleus !
PLEASE LOAD MORE VIDEOS....!
you explain the content with ease! i´ve been looking for some didatic explanation in portuguese (my mother tongue) but i haven´t found it ...so i came across to your video and i found it really well explained. Congrats and keep it going! you´re good at this.