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Answer:
Dr. Asaji Tetsuo kindly answered the above question.
The difference between NaCl and H2O
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We might be able to say that salt is the gigantic molecule of NaCl. Unlike the H and O in a water molecule
H2O, Na and Cl do not have “arms for bonding”. Instead, Na has a positive charge, and Cl has a negative charge. The charge does not have a certain direction like an “arm”.
So the force of aggregation is isotropic electrostatic attraction.
We call it “salt” when they aggregate with each other until we can look at them. At this level, almost an infinite amount
(1023) of Na and Cl are aggregated. |
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Salt crystal
Courtesy of "My favorite chemistry experiment"
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Existence of NaCl diatomic molecule
However, we cannot conclude that there is no electron transfer at all from Cl- to Na+. In other words, the electron distributions of isolated Cl- and Na+ would be different from Cl- and Na+ in a crystal. It could be possible to create a NaCl molecule, though I don’t know how.
The molecule NaCl is gaseous, so it is different from solid salt. We can say that the bonding of NaCl diatomic molecule is a covalent bond whose polarity is very large. The ionicity of the bonding was estimated to be 70 – 80 %. The distance from Na+ to Cl- in a salt crystal would be a bit longer than that of NaCl as a diatomic molecule. This implies that the ionicity of Na+ and Cl- in salt would be higher.
Acknowledgement
Dr. Asaji Tetsuo
He is studying solid-state physics using nuclear quadruple resonance (NQR).
This article is translated by Chemistryquestion.com from the original article in Chemistryquestion.jp. Please let us know if you find any errors.
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