New answers tagged molecules
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Let the number of total valence electrons, including charges (ions) be ($V$).
The number of total electrons required to complete octet/duplet is given by ($T$) = $(2 × \ number \ of \ H \ atoms) + (8 × \ number \ of \ other \ atoms)$
The number of bonding electrons is given by $B = (T-V)$
The number of bonds is given by = $\dfrac{B}{2}$ $=$ $\dfrac{(T−V)}{...
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The given compound, 1,2-dimethylcyclobutane has two chiral centers, and hence, has maximum of $2^2 = 4$ stereoisomers. However, as shown in the scheme below, the cis-isomer has a plane of symmetry, and as a consequence, it is a meso-isomer:
However, trans-isomer can exists in two forms: (1R,2R)-1,2-dimethylcyclobutane and (1S,2S)-1,2-dimethylcyclobutane (...
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Aside apparent possibilities of a made-up structure or structure being a fragment ripped off from a larger heterocycle by the designer, there is a third one.
Let's pretend the black dash next to the label ‘N’ on the bottom is a minus sign.
Then we have 2,3,4‐tricyano‐1H‐pyrrol‐1‐ide $\ce{C7HN4-}$:
I haven't found this exact structure, but a more symmetrical ...
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Dextrose equivalent $(DE)$ is a measure of the amount of reducing sugars present in a sugar product, expressed as a percentage on a dry basis relative to dextrose (glucose). Commercial sugar products are generally characterized by their dextrose equivalent $(DE)$ value (Ref.1). The theoretical definition of $DE$ is given by:
$$DE = \frac{\text{Reducing power ...
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The easiest approach would be to utilize the b-factor column in the pdb-file as suggested in the pymol wiki:
https://pymolwiki.org/index.php/Color#Reassigning_B-Factors_and_Coloring
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According to the Gold Book and IUPAC 1988 Recommendations (Ref.1):
Hydron: The general name for the cation $\ce{H+}$; the species $\ce{H-}$ is the hydride anion and $\ce{H}$ is the hydro group. These are general names to be used without regard to the nuclear mass of the hydrogen entity, either for hydrogen in its natural abundance or where it is not desired ...
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The chemical prefix "hydro" is a confusing one, because the Greek root "hydro" in English words usually refers to water, as in "hydrophilic" (hydro=water; philic=loving) for example. Another example relevant to this question is "hydrogen" (hydro=water and gen=making).
In chemical names, however, "hydro" is a ...
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