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## Electrons clumpsy paths

As we have learnt that as the electrons move towards higher shells it attains more energy. But according to aufbau’s principle, orbitals are as follows 1s < 2s < 2p < 3s < 3p < 4s < 3d Hence electron when it will be in 3p orbital will directly jump to 4s and then it […]

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## Where are the tetrahedral voids and octahedral voids located in an FCC?

A crystal is made up of atoms X, Y, and Z. Atoms X are in FCC packing, Y occupy all octahedral voids and Z occupies all the tetrahedral voids. If all the atoms along two body diagonal are removed, find formula of crystal. Since there are 4 atoms in FCC, number of X=4. Tetrahedral voids […]

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## What is equilibrium

Can we have any random combination of temp and pressure having constant volume of gas reaction to achieve equilibrium. Please don’t flag. Reply if need more clarification 🙏. What I mean is if given constant conditions 1 atm pressure and 298k temperature without changing the volume i.e volume is also constant can equilibrium be achieved […]

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## How would one determine the temperature needed such that hydrogen peroxide will start to decompose?

Hydrogen peroxide decomposes at room temperature and so I was wondering what temperature is sufficient for this decomposition to occur. Can someone explain how we can determine this? (theoretically or experimentally – but to me it seems like it would be easier to determine experimentally) I don’t know if there is a technical word for […]

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## When does replacing a double bond with a lone pair result in a valid resonance structure?

Take molecules A and B below. In A, we can move the electrons from the green pi bond into a lone pair on oxygen, then move the blue lone pair of electrons from the other oxygen to form a new pi bond, and this is a valid resonance structure. But in B, I was told […]

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## Why c/a ratio for Ti, Mg and Zn deviates from 1.6333?

What is the reasons for the deviation if any from the ideal c/a ratio(1.633)of these Hcp packing.??

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## How to reduce the surface tension of molten metals?

I’d like to reduce the surface tension of molten metals to reduce air bubbles by casting them like in this video with plaster. Actually the goal is to be able to cast gold without bubbles, but I guess it will be a long journey and better to start with cheaper metals. With a quick search […]

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## How to calculus the critical time of Dissolved oxygen sag curve

Denote $DO_t$ to be the dissolved oxygen amount of the river in time "t". Denote $DO_0$ to be the dissolved oxygen amount of the river in the beginning. then the dissolved oxygen rate is $D=k_1\frac{d DO_t-DO_0}{d t}$. the reoxidation rate is $D_{re}=-k_2\frac{d DO_t-DO_0}{d t}$. then the total dissolved oxygen rate is \$D_t=D_0+D_{re}=k_1\frac{d DO_t-DO_0}{d t}-k_2\frac{d DO_t-DO_0}{d […]

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## Change in surface tension of soapy water as oil is added

I am wondering about how the surface tension of clean soapy water changes as oil is added to it? Is the change gradual or is it abrupt as the amount of oil added exceeds the amount of soap available to surround the oil. So if the surface tension of clean soapy water is 25 dynes/cm, […]

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## Thermodynamics- How are various property tables made?

I’ve always been curious about how different thermodynamic property tables are made. It’s really interesting to me. I want to know how different things such as critical properties and variations of properties of different systems are determined. I’m not familiar with statistical physics, but any derivations using it would be great for future reference.