Chirality of synthetic nitrogen fertilizers ... harmful?

[Did67]

Let's always try to be precise: there is no "left form" of a substance. It does not mean anything. It is about the fact that a solution of this substance, crossed by a polarized light, sees its plane of polarization deviated to the left, if it is "levorotatory".

[In simple: the light being waves, these vibrate, for a natural light, anarchically, in all the directions; polarized light is light in which all waves vibrate in the same plane - very exactly parallel planes; as if they had been passed through a comb. By crossing the solution, this plane is deviated either to the left, in the "levorotatory" form of a substance, or to the right in the "dextrorotatory" form. Calling an enantiomer D or L is, on the other hand, conventional - it depends on the position of the radicals on the first carbon].

[izentrop]

Molecules have a shape that can be represented in perspective by a 3D representation, in drawing by the representation of Cram http://www.faidherbe.org/site/cours/dup ... p.htm#cram.
When it is crystallized, it is plainly visible:

"Enantiomeric sodium ammonium tartrate crystals separated by Pasteur."

[gek]

As a chemist, I can confirm that this chirality thing is bullshit. Nitrates and ammonium are not chiral molecules because there are elements of symmetry in these molecules. To be chiral it is necessary to be asymmetric (bond with 4 different groups for a tetrahedral carbon called sp3 typically).

It reminds me of those ads in which we use learned words to impress: active oxygen lye, regenerium XY ...

Yes there are "great scientists" who often derail by going outside their field of expertise. Montagnier (nobel prize) is now one of the ardent defenders of the memory of water (he performs physics and bio experiments to "prove" it), Paulin (also nobel) was convinced of being able to cure all cancers by stuffed with vitamin C, Pr Joyeux oncologist surgeon (struck off for some time) who explains all-out the harm of vaccination. This phenomenon has been dubbed the Nobel Prize Syndrome:

http://www.sceptiques.qc.ca/dictionnair ... sease.html

[izentrop]

Hello,
And what does that mean for a non-chemist? We are talking about chirality, but unstable?

The amines of the type RR′R "N and RR′NH are chiral, but it is not possible to obtain them in the form of a single pure enantiomer because of the rapidity of the nitrogen inversion except in cases exceptional as with invertomers; the situation is however very different for the ammonium salts, RR′R ″ HN + and RR′R ″ R ‴ N +, or the amine oxides, RR′HNO and RR′R ″ NO, which are optically stable Likewise, the corresponding chiral phosphines (RR′R ″ P and RR′PH), sulfonium salts (RR′R ″ S +) and sulfoxides (RR′SO) are optically stable. https://fr.wikipedia.org/wiki/Inversion_de_l%27azote

[gek]

Hello,
And what does that mean for a non-chemist? We are talking about chirality, but unstable?

The amines of the type RR′R "N and RR′NH are chiral, but it is not possible to obtain them in the form of a single pure enantiomer because of the rapidity of the nitrogen inversion except in cases exceptional as with invertomers; the situation is however very different for the ammonium salts, RR′R ″ HN + and RR′R ″ R ‴ N +, or the amine oxides, RR′HNO and RR′R ″ NO, which are optically stable Likewise, the corresponding chiral phosphines (RR′R ″ P and RR′PH), sulfonium salts (RR′R ″ S +) and sulfoxides (RR′SO) are optically stable. https://fr.wikipedia.org/wiki/Inversion_de_l%27azote

The amines mentioned in this text are asymmetric (it does speak of all different substituents on the nitrogen atom), in this case we can speak of chirality. The unstable aspect comes from the fact that the molecule oscillates very quickly between its left and right shape at room temperature and therefore the time to measure the deviation of the plane of polarization of a polarized light the molecule has made a high number of inversions and we observe the mean deviation which is zero.

For an ammonium, there is no longer this inversion problem but once again to be chiral, an ammonium must have different substituents on the nitrogen (R, R ', R' ', H for example). the ammonitrate which is the most common source of conventional nitrogen is nitrate NO3- and ammonium NH4 +, therefore a symmetrical and achiral ammonium ...