# Tag Info

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The reasoning you utilized for comparing the bond angles of $\ce{NH3}$, $\ce{NF3}$, and $\ce{NCl3}$, while sensible, is simplistic and works best only for a few cases where weighing the factors of steric repulsion against bond pair-bond pair repulsions is feasible. It seems that you have encountered this very problem in the case of comparing the bond angles ...

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The most obvious method is single crystal xray crystallography, of course, and for simple molecules, IR and microwave spectroscopy in the gas phase can be used. For many complex (e.g. bioorganic) molecules, this fails, but there are two (afaik) last hopes to help solve/prove structures if they don´t crystallise and the usual NMR spectroscopy with added ...

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Coordinate bonds are covalent bonds where both bond electrons stem from only one of the two bond partners. They are formed when a Lewis base donates two electrons into accepting orbitals of the Lewis acid. That's not what you're looking at in this case, where both $\ce{P}$ and $\ce{O}$ contribute one electron to the common $\sigma$ bond. The interesting part ...

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You may map the electron density around an atom will find regions where this probability is relatively high. Similar to a hiking map where lines mark the same elevation in a terrain, contour maps offer a representation in 2D, where the lines mark regions of same electron density. You find these used in quantum mechanics (like the ones below), or in ...

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First, it's important to understand that the simple integer hybridization labels sp, sp2 and sp3 are gross approximations and only accurately describe the electron density of simple symmetric molecules like $\ce{BeH2}$ and $\ce{CH4}$. Atoms in more complex molecules (even something relatively simple like $\ce{H2O}$) cannot be described accurately using these ...

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Bond order is the number of electrons shared between two atoms divided by two. There are a few things that limit how high a bond order can possibly go, however. First, atoms can usually only form bonds until their valence electron shells are filled (any more electron would be unstable). The heaviest elements, those of periods 6 and 7, have at most 32 valence ...

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A simple way to compare the $\mathrm pK_\mathrm a$ of $\ce{-NH3+}$ and $\ce{-COOH}$ in such a scenario would be to assume the situation when the amino acid becomes a zwitter-ion. A zwitter-ion is a molecule that has both positive and negative charges on it. In an amino acid, the $\mathrm {pH}$ at which this is seen is known as the isoelectronic point. Let's ...

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A force is the derivative of a potential energy: $$\vec{F} = -\vec{\nabla} U$$ If you choose to apply a continuous force to stretch a bond until rupture, the force will need to exceed the restorative force (as described say by Hooke's law for small displacements from equilibrium) due to mutual attraction of the atoms. The maximum value of that restorative ...

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Why does the free element choose a specific element to bond and how do I know what element it'll bond with? Science has more answers related to "how" rather than "why"? Can we answer why do you have five fingers and two eyes? Not as yet, but scientists can talk a little bit how the eye works. Similarly, your open ended query depends on ...

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I highlighted the some of your attempts: $\ce{H_d}$ has $\mathrm pK_\mathrm{a} \approx 9$, so it will not be the most acidic. This assumption is correct. For aspartic acid, $\mathrm pK_\mathrm{a}(\ce{H3N+}) = 9.6$. $\ce{NH3+}$ has very high -I effect but no mesomeric effect, so $\ce{H_c}$ appears to be quite acidic. But at the same time it is at the ...

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To add an analogy: imagine you have a friend who married a jerk, and you wonder why. After all, there are so many people in the world, nearly $10^{10}$ at the latest count! How do people decide who to pair up with? Well, in that case it might have been due to a chance encounter at a mixer at which both got slightly tipsy (and believe it or not he happened to ...

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EDIT (after title edited): $\ce{HBr}$ doesn't have stronger interaction than $\ce{CH2NH2}$, but it has dipole-dipole interaction as the strongest forces between it's molecules, which is obviously weaker than H-bonding. Hydrogen bonding is the strongest intermolecular attraction. It is a type of dipole-dipole interaction1, but it is specific to Hydrogen. In ...

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The pictures we use can inspire questions that are more complicated than they have to be. I like the hamburger picture of ferrocene: OK, there are some people who like a picture of some electron densities: Without going into the mathematics of all the orbitals, you can see that the filled orbitals on cyclopentadienide ion will have two lobes to donate into ...

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