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Oxygen very much does form bonds in which both electrons come from the oxygen atom. Examples include: 1. The $\ce{H3O^+}$ ion at the center of the solvated proton in aqueous acids, also available as salts of some of the strongest acids such as $\ce{(H3O)(ClO4)}$ 2. Carbon monoxide, with its triple rather than double bond. 3. Ozone, in which the oxygen ...


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I found a nice figure and the relevant statement in a paper by Frenking and Krapp (Unicorns in the world of chemical bonding models, 2006, https://doi.org/10.1002/jcc.20543): The crucial term which is responsible for repulsive interactions in chemical bonds except in two‐electron systems such as H2 is the Pauli repulsion. The three terms (a) ...


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The larger angles can simply be explained as a result of repulsion between the larger atoms of $\ce{Br}$ and $\ce{Cl}$. Hydrogen atoms in $\ce{PH3},$ as the are so small, experience less repulsion as compared to $\ce{Br}$ atoms in $\ce{PBr3}$ or $\ce{Cl}$ atoms in $\ce{PCl3},$ therefore the larger bond angles in $\ce{PBr3}$ and $\ce{PCl3}.$


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As you are probably aware, generalizations like "$\ce{BCl3}$ is a stronger Lewis acid than $\ce{AlCl3}$" can be problematic, as the results can be dependent on the base used and the conditions (eg solvent choice). That said, a common context for this ranking is with respect to carbonyl bases, such as in a Friedel-Crafts acylation. For these bases, $\ce{...


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The Hamiltonian for the collection of charged particles (electrons and nuclei) comprising a pair of molecules or ions has terms describing the kinetic energy of individual particles and pair-potential terms describing Coulombic interactions, that is, all interactions between particles are Coulombic. Where a Pauli repulsion term can crop up is when ...


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From a structure diagram alone it is hard to determine these interactions. The reason for this is that important structural parameters are stretched or shortened in order to flatten the molecule for a 2D drawing. In a first order approximation a molecular modelling kit based on balls and sticks could already be very helpful. It'll let you approximate the 3D ...


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Generalisations are impossible. There are many examples of strong and weak bonds in both ionic and covalent compounds There are a number of problems with the question. One is that there bonding is not an either/or concept: there is a something of a continuum between "pure" ionic and "pure" covalent bonding. There is also a lot of confusion about what sort ...


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Part of the reason for many answers is that "stronger" can be different things. If we consider a typical two-electron bond between two atoms A and B, it can break in three ways: 1) 1 electron can stay with A and one with B: $\ce{A-B -> A. + B.}$ This is called homolytic bond cleavage. 2) Both electrons can stay with A: $\ce{A-B -> A- + B+}$ This is ...


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Consider the three hydroxyphenols catechol (ortho-hydroxyphenol), resorcinol (meta-), and hydroquinone (para-). All three engage in hydrogen bonding with their hydroxyl groups. But they differ in polarity. Hydroquinone, with its hydroxyl groups symmetrically placed on opposite corners of the benzene ring, has a limited (average) dipole moment between two ...


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Lattice energy Now, according to wikipedia, NaCl has a lattice energy of −756 kJ/mol. First, we have to understand the term lattice energy. Here is the textbook explanation (Fleming: Physical Chemistry): The lattice energy is the energy required to separate the ions in an ionic lattice so that they are at infinite distance (but still ions). This would be ...


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