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Thanks!

Thanks!

It depends on the unit used for R. I use units for R that result in density expressed in g/L, which is a common way to express gas density. If you use R with m³ instead of L, then you would have to express molar mass as kg/mol in order to get to kg/m³. If you notice that there are 1000 g in 1 kg, and there are 1000 L in 1 m³, that means 1 g/L = 1 kg/m³. So whatever density you get from the math that is expressed as g/L, you can use the same value to express it as kg/m³. So for example 3.07 g/L = 3.07 kg/m³, etcetera.

@@CrashChemistryAcademy when I solved the equation I got kg/L so how can i make it kg/m³

What unit for R are you using?

Yes it's confusing, and kudos to you for noticing! The short answer is there are not enough elements to get to higher n sublevels. n is the MAXIMUM number of sublevels possible for that given n, it does not dictate that there WILL be that amount of sublevels. The periodic table has 118 elements so far, and each neutral element has the amount of electrons equal to its atomic number. For elements of n = 1 and 2, they can fill all sublevels possible. For n = 3 and 4, it is not until the the following periods (n + 1) that the 3d and 4d sublevels begins to fill, and for n = 5 and 6, it is not until two periods later (n + 2) that 5f and 6f begin to fill. For any element in n = 6, there would have to be elements in n = 8 to get to 6f, but there is no n = 8, which would begin with element 119, which does not exist. Element 121 or 122 would begin to fill the 5g sublevel, so you'd have to get to around element 140 or so before 6f begins to fill, and something far beyond to get to 6h. So to finally answer your question, yes, for n = 7 elements, the maximum sublevel goes to i, but now we would have to be somewhere in atomic number 200s to get enough electrons to fill 7i. This PT structure comes out of the quantum mechanical model, first proposed by Schrodinger in 1926.

@@CrashChemistryAcademy Thank you so so much for taking the time to explain this with such clarity!! People like you are a blessing for students. This finally gave my brain peace. Thank you once again 🙏🤝

You’re welcome! I’m glad it helped.

The mathematics of the Schrödinger equation (1926) describes the electron's behavior in an atom. The math is based on the electron behaving as a wave, with the wave function describing 1) areas within which there is a high probability of finding an electron (the orbital), and 2) areas within the orbital where there are high probabilities and zero probability of finding the electron, called antinodes and nodes, respectively. The electron is not characterized as having any trajectory because that violates the Heisenberg uncertainty principle, which states we cannot know both the momentum (path or trajectory) and the location of a particle simultaneously. If we knew the electrons trajectory, that would mean we would also have information about its specific location and direction, which cannot happen in the world of physics. The uncertainty principle is considered a fundamental part of how particles behave in the universe. So the electron cloud is simply areas of higher and lower (zero) densities of negative charge that constitutes the orbital. After almost 100 years of 10,000s+ physics experiments, none have shown the mathematics of the Schrödinger equation to be incorrect, and all those experiments have shown the math to correctly describe electron behavior.

@@CrashChemistryAcademy That is understood, but mathematics alone does not verify what is a reality. Observations and experimentations do. Mathematics is a support of what has been substantiated to be true. That is why in physics there are theoretical physicists. Theoretical because they deal with the mathematics of reality, of subjective and objective truths.

Yes, agreed, and that motivated(s) physicists to do all those experiments on quantum mechanics over the last 100 years.

The video presents only the wave idea of light energy (electromagnetic), which is easy to connect to a periodic function, and that makes it more accessible for the connection to frequency and wavelength, which is straightforward for a periodic function. However, a single pulse of light, by which I assume you are referring to a photon, when not disturbed, exists as the spread out uniform wave as shown in the video. There would be no distortion as you have described, which belongs in the classical physics world. In the quantum world, as with so many other phenomena, when the pulse, or photon, interacts with matter, its properties seem to change to that of a single particle of light. The light has not changed, just our interaction with it has changed how we perceive it. The photoelectric effect is a prime example of this interaction. I am certainly not an expert in this, and I have always found light to be pretty mysterious (more than other quantum phenomena...), but that is my take on it. Not sure if I answered you question, hope that helps.

Not bad, you?

I have not heard of him. The amount of global warming deniers among physical scientists has always been quite small, far far smaller than the media would have us believe, and in the last 40 years that amount has declined to close to zero physical scientists that question global warming. I guess this person is one of them. Perhaps his faculty for cognitive dissonance was never developed.

I looked him up on youtube and watched an hour+ lecture from a few months ago. Like many charlatans he is adept at mixing fact and fiction. For an hour lecture it was interesting how little of substance was said. Also interesting was his pedigree-- one does not take lightly what a Princeton physics prof has to say, but in this case he seems to not really understand the data (???). As he said, he is not a climate scientist. Interestingly, a large percent of the physical scientists over the years who were climate change deniers were physicists. That seems strange. One I remember was Freeman Dyson, a hard core climate change denier, who was put on a climate change panel under the G. W. Bush admin in the early 2000s. The panel was made entirely of businessmen who were climate deniers, with Dyson the only scientist. The interesting part was that apparently not long before the formation of the panel, Dyson had a change of heart, and while on the committee he expressed his understanding that the climate was indeed changing, and he was immediately dismissed from the panel.

Thanks!! (for the clue) 😊❤️

The idea of "heat rising" comes from buoyancy of hot versus cool gases. I realized my illustration would reinforce that misconception after I put it on youtube. Heat will only move from a warmer system or object to a cooler system or object that are in contact with each other, without regard to the flow being up/down/sideways. So if the two blocks were reversed, hot on top and cold on bottom, the hot block on top would lose KE to the bottom block. They would reach thermal equilibrium by the heat flow going down, not up. Same with inserting some material such as copper foil between them side by side. The heat will flow from hot to cold, first to the copper, then to the other block, until thermal equilibrium is reached. Any contact of the hot block with a cooler material below it such as wood or the ground gives the same flow (down), from hot to cold. Of course we can assume it is surrounded by air as well, so heat would also flow to the air. The buoyancy explanation of heat rising has to do with different temperature gases. For example as hot gases are produced from a flame, they quickly spread out due to high KE and become less dense than the cooler surrounding air. This makes the hot gas very buoyant and it quickly rises upward. Another important example is if you hold your hand over a hot object, say a hot block of iron. You feel that heat above the block for the same reason explained with the gases. The block transfers KE to the surrounding air, which now decreases in density and becomes buoyant and rises to where your hand is. If you put your hand to the side or underneath the block (not touching it) you do not feel its heat. HOWEVER if you hold the hot iron in your hand, with your palm under the block, now, because the two surfaces are in contact, you will feel the heat flowing down into your hand. We have all experience holding a hot object, so that is a great example of strictly hot to cold heat flow, showing that the idea that heat always rises is a misconception, that in fact heat will go in the direction of hot to cold for two objects in contact.

YES! You have answered your own question-- all orbital sublevels converge onto the nucleus, and so all orbitals overlap at some point. However, as you stated, electrons in different orbital sublevels have different energies, and this is how electrons in different sublevels can be distinguished in the area of the overlap-- by the different energies they possess. In the area of overlap, if an electron has a 1s or 2s or 2p energy, then it is in the 1s or 2s or 2p sublevel.

@@CrashChemistryAcademy So the electrons of both orbitals can exist in the area of overlap but can be distinguished by their different energies? (Sorry if I'm disturbing you, I haven't studied Hinesburg Uncertainty Principal yet.)

@@CrashChemistryAcademy Um, am I correct?

Yes, that is correct! The orbital is a manifestation of the energy of the electrons. The energy of the electrons are described by the mathematics of Schrodinger's 1926 equation. We interpret that math as a three dimensional space of high probability of where electrons of a certain energy exist. So two overlapping orbitals are distinguished from each other by the energy of their electrons.

no problemo. Thanks for watching.

Great!

Thanks, I appreciate it!

During earth's history, the ocean has absorbed about 30% of atmospheric CO2. These large amounts of CO2 have dissolved into the ocean and have become stored there via a variety of processes, including the resulting hydrogen carbonate (which has a long half life in the ocean), phytoplankton and plant incorporation of the carbon in CO2 as a large array of biological substances, CO2 can be incorporated as mineralized rocks on the sea floor, etc. All of this was essential for the natural unfolding of the evolution of the climate and life on earth. This was all occurring to a large extent as an equilibrium-- the processed was balanced. However, due to the sudden large increase in atmospheric CO2 in the last 150+ years, the equilibrium has been drastically thrown off. If the amount of CO2 in the air were leveled off today, it would take many many millenia for the ocean to come back to an equilibrium. Regarding crushed shells-- they are made of calcium carbonate, CaCO3. When in contact with water, a tiny percent of CaCO3 proceeds with the following reaction: CaCO3(s) + H2O(l) <-> Ca2+(aq) + HCO3-(aq) + OH-(aq). Any added aqueous OH- ions will increase the pH of the water. The double arrow is there due to this being a reversible reaction. The equilibrium constant for the reaction is 4.7 x 10−9 at 25°C. What that means is that one out of every 4700000000 CaCO3 molecules will proceed with the reaction, while the rest remain as CaCO3. So not very effective for large scale reversal of acidification.

@@CrashChemistryAcademy still a lot to take in. But what about the White Cliffs of Dover,, isn’t that Calcium carbonate? And I’ve seen videos,where it’s eroding and falling back into the ocean. You would think that the ph would be higher around the straits. I haven’t found any numbers yet. I enjoy the study and your video,,,the politics going on make me nervous 🌳

Yes the white Cliffs are made of CaCO3 and there is a localized increase in pH where cliff chunks fall in the water, but the slightly raised pH water will mix with the rest of the ocean (especially in the rough English Channel waters) and dilute out that pH increase. Note also that this reaction is slowed down due to water only reacting with CaCO3 on the surface of the chalky chunks. The majority of the CaCO3 is below the surface of the chunk, and so has to wait its turn to come into contact with water as the water slowly reacts with the surface of the cliff debris. By the way, the CaCO3 tablets used in pharmaceuticals to reduce stomach acidity are designed to break apart quickly in the stomach, and that is aided by the very acidic pH of the stomach of around 1 to 2.

I would suggest going through the examples in the video slowly, analyzing each step for why it is happening-- try to explain it to yourself, then listen to how it is explained in the video to see if you are getting it. Don't be afraid to go back further and make sure you understand what leads up to mass-mass problems.

3 - (-2) = 5

Yes, Please use them as you need. I appreciate any use by educators!

By convention (although not necessary) the coefficient has the decimal after the first number. If changing the decimal location, the exponent also has to change to maintain the value of the number. So I changed the original scientific notation from 18.2 x 10^-7 to 1.82 x 10^-6 to conform to the convention.

Radiative scattering from clouds is termed albedo. Albedo is mentioned a few times in the video. Cloud formation itself is certainly important to warming, but the complexity of cloud formation warrants a separate video.

@@CrashChemistryAcademy The concept of albedo applies to all objects not just clouds. You did mention this concept. I am specifically referring to the radiative scattering and formation mechanism of clouds this video does not mention. The albedo of a cloud is integrated from the scattering cross section derived from those mechanisms. These mechanisms are the most essential for computing the overall albedo of the earth. However these mechanisms are extremely complex, chaotic and largely unknown.

Thanks much for your input.

Thanks for watching!

YER WEELLLLCOOOOOOOOOOMME! 😊 Thanks for watching!

The cliffs are white due to their being composed primarily of calcium carbonate, CaCO3. When in contact with water, a tiny percent of CaCO3 proceeds with the following reaction: CaCO3(s) + H2O(l) <-> Ca2+(aq) + HCO3-(aq) + OH-(aq). Any added aqueous OH- ions will increase the pH of the water. The double arrow is there due to this being a reversible reaction. The equilibrium constant for the reaction is 4.7 x 10−9 at 25°C. What that means is that one out of every 4700000000 CaCO3 molecules will proceed with the reaction, while the rest remain as CaCO3. So yes there is a localized increase in pH, but the slightly raised pH water will mix with the rest of the ocean and dilute out that pH increase. Note also that this reaction is slowed down due to water only reacting with CaCO3 on the surface of the chalky chunks. The majority of the CaCO3 is below the surface of the chunk, an so has to wait its turn to come into contact with water as the water slowly dissolves the chunks of cliff. The CaCO3 tablets used in pharmaceuticals to reduce stomach acidity are designed to break apart quickly in the stomach, and that is aided by the very acidic pH of the stomach of around 1 to 2.

Thanks! I will look into it.

Thanks 👍