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Here are my calculations. Are they wrong ? Δ$\lambda = 9.2·10^{-14}$ m. Δ$\nu = c/Δ\lambda = 3·10^8 ms^{-1} / 9.2·10^{-14} m = 3.3 ·10^{21}s^{-1} $; Δ$E = hΔ\nu = 6.6·10^{-34} Js· 3.3·10^{21} s^{-1} = 2.2·10^{-12} J$ Δ$t = (h/4\pi) /ΔE = 6.6·10^{-34} Js/(4\pi·2.2·10^{-12} J) = 2.3·10^{-23} s$


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The only restriction on your equation is that the system is at constant temperature. The system can be open or closed, the pressure does not have to be constant, and any type of work is allowed. Let's start with the basic definition of G in terms of H, which is completely unrestricted: $$G \equiv H-TS \Rightarrow dG = dH - d(TS) = dH -TdS -SdT$$ Then, to ...


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It is correct. But usually the measured values are much higher than $10\ \mathrm J$ or $100\ \mathrm J$. They are more frequently $1000$ times higher, being around $10\ \mathrm{kJ/mol}$ or $100\ \mathrm{kJ/mol}$.


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As pointed out in the comments the rigid rotating molecule only gains kinetic energy when it rotates not potential energy. The degeneracy describes the fact that some levels have exactly the same energy and this depends the value of the angular momentum rotational quantum number $J$. The number of degenerate levels is given by the multiplicity $2J+1$. The $...


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I have two questions... Why does a molecule "gain potential energy" when it rotates? Does it want to stop rotating for some reason? What do degenerate energy levels correspond to physically in terms of the molecule's rotation? Do you remember the Newton's law of motion? A body in motion will always remain in motion until and unless there is a ...


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You can think about this problem from the definitions of surface energy. The surface energy quantifies the disruption of inter-molecular bonds that occurs when a surface is created The composition or structure of a surface depends on how the bulk crystal has been cut. The electronic structure (or number of dangling bonds) depends on surface composition ...


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You may simply say that energy is needed to break a bond. Breaking a bond is endothermic. So the inverse is exothermic. Energy is released when a bond is formed. Apparently you want to just discuss what is happening when an electron approaches a proton from far away (x1 in your drawing) to a shorter distance (x2). The electron is supposed to have no ...


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Start by looking at the Hamiltonian for a molecular system \begin{equation} \label{eq:coulomb_hamiltonian} \hat{H} = - \sum\limits_{α=1}^{ν} \frac{1}{2 m_{α}} \nabla_{α}^{2} - \sum\limits_{i=1}^{n} \frac{1}{2} \nabla_{i}^{2} - \sum\limits_{α=1}^{ν} \sum\limits_{i=1}^{n} \frac{Z_{α}}{r_{αi}} + \sum\limits_{α=1}^{ν} \sum\limits_{β > α} \...


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Lattice energy is a function of the radius ratio, which when tends to 1, improves the packing efficiency of the molecule. Here the radius ratio of the chloride ions and aluminium ions is much closer than the fluoride ions. You could think of this from the born habers cycle also. Where the electron affinity of chlorine is higher, which leads to overall higher ...


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Find compounds that emit light under photolysis. As that may involve radical production pathways, one can also try to apply sonolysis to the same compounds as: H2O (with dissolved O2, N2,..) + Sonolysis -> *H + *OH Reference source: 'Free radical formation from sonolysis of water in the presence of different gases'), to quote: "In this case, O2 reacts ...


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In order to make the phase transition, you need to supply your sample molecules with an additional amount of kinetic energy (i.e., the heat of fusion or vaporization) to overcome their intermolecular bonding. This however means that after the transition, your system contains more internal energy than before. That additional energy is encoded in the vertical ...


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Chemical potential is a portion of water potential, but not all of it. Factors like gravity and bulk fluid properties also affect the water potential. Water potential is typically used for macroscopic quantities of water, so it is more natural to consider the amount of water by volume rather than the number of molecules. If you convert the number of ...


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According to German Wikipedia water potential is defined as $$\psi := \frac{\mu - \mu_0}{\bar{V}}$$ where $\mu_0$ is the standard chemical potential (usually pure water at atmospheric pressure at a specified reference height), and $\bar{V} \approx \pu{18 cm3 mol-1}$ is the the molar volume of pure liquid water. This means that water potential $\psi$ is ...


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