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1

You said "Fermi level is constant throughout the junction" - that's correct. But fermi level is "A" (see top right in the table). So A is constant (you can set it to zero if you like). B is not constant.


1

This is an interesting question. If you have two isolated atoms (and they don't need to be H) in the gas phase moving towards one another and colliding, is quite straightforward as we are in the situation that total energy is conserved. If we assume that one atom is stationary it then is easier to describe what happens and makes no difference to the answer. ...


2

There are 4 vibrational modes in a molecule like CO2 like you are considering. These would be a symmetric stretch, an antisymmetric stretch, and 2 bends (just like your animations). In case of non linear molecules there is only one vibrational bend: Lets consider H2O. You might be tempted to think that the same argument of two bends should apply here, but on ...


2

Water vapour can be said to be one of the the most important contributor to the greenhouse effect. To estimate its potentiality is a bit complex exercise as the absorption ranges of wavelengths in the infra-red region overlaps for different green house gases. In some of these overlap regions , the atmosphere already absorbs 100% of radiation, ...


2

This is a more general answer. Atoms and molecules are quantum mechanical entities. This means that the "shape" of atoms depends on the solution of quantum mechanical equations, which give probabilities for locating in space the electrons that are bound to the nucleus of the atom with the electric potential provided by the protons of the nucleus. The ...


5

The water molecule is neutral on overall basis, i.e: the water molecule as a whole has no net charge. The water molecule is not linear rather it has a bent shape with two hydrogens on the same side. This happens because of the lone-pair-bond-pair repulsions. The oxygen has is a more electronegative element than hydrogen, i.e: oxygen has high electron-...


1

Materials that seem homogeneous often have internal strains, or voids, or even inclusions. Under stress, rather than uniform deformation (bending), those flaws may undergo brittle fracture, or stretch excessively, or become chemically active. A cosmic ray can create internal damage, a particle decay track. So, after some kinds of handling (bending, ...


0

Factors affect the time (i.e. from start to the time of equilibrium state where the following processes are sustainable: flame heat up wax, liquefied wax being pulled up, evaporated, wax vapor mixes with air, burn and produce heat) are followings, - size of wick (the larger, the more heat it can produce) - size of wick (for capillary flow) - wax type (...


0

There's a type of alloy called interstitial alloy, which might increase the density of the metal, while perhaps not expanding its volume, by introducing small atoms that can fit


0

Copper is quite a dense metal at 8.96. Both the stable copper oxides are lower density. I do not believe any surface treatment could increase the bulk density of pure copper, unless there are cavities in the material. The only way apparent density might increase is if the volume is assumed constant and the treatment causes the surface to adsorb external ...


1

Your equation for gas permeation mostly applies to hydrogen, which will dissociate into hydrogen atoms before entering the material. For nitrogen (major component of air), the equation has no square roots. Nitrogen permeation is extremely slow; if the box is welded shut and there are no cracks, then this process will be negligible, even over a 10-year period....


0

There are lots of emission and absorption lines – at different energy scales. Atomic spectra, vibrational spectra, rotational spectra, and so on. For each of them, one may discuss millions of molecules in principle (most of the large number are organic molecules). The amount of data to cover "everything" is clearly unrealistically huge. But any subset of ...



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