The Markovnikov rule expresses the regioselectivity to be expected in the addition of unsymmetrical reagents (such as HX) to unsymmetrical alkenes (such as H2C=CHR).
Heating solid hydrogen sulfite salts (shown by the equation above) or passing gaseous sulfur dioxide into their aqueous solutions produces disulfites.HSO3−(aq) + SO2 → HS2O5−(aq) Disulfite ions possess a sulfur-sulfur bond and are therefore unsymmetrical.
Practically, however, each image point occupies a volume of finite size and unsymmetrical shape, causing some blurring of the whole image.
The subsequent response to changing load and the small vibrations executed when the strip is struck lightly are characteristic of the new unsymmetrical shape.
However, because of the many unsymmetrical geologic factors influencing intensity, the curves are often far from circular.
(Alar is listed as a carcinogen in California, but it and its metabolite, unsymmetrical dimethylhydrazine [UDMH], are considered probable carcinogens by the U.S. Environmental Protection Agency).
Open clusters contain from a dozen to many hundreds of stars, usually in an unsymmetrical arrangement.
In the hydroboration and hydrosilation of an unsymmetrical alkene, the boron or silicon binds to the carbon atom that has less-bulky substituents, and the smaller hydrogen atom binds to the carbon atom that has bulky substituents—(CH3 2C in the above equations.
Markovnikov rule, in organic chemistry, a generalization, formulated by Vladimir Vasilyevich Markovnikov in 1869, stating that in addition reactions to unsymmetrical alkenes, the electron-rich component of the reagent adds to the carbon atom with fewer hydrogen atoms bonded to it, while the electron-deficient component adds to the carbon atom with more hydrogen atoms bonded to it.
We were reading in a recent Times about the research uses of the Titan 11, one of the nation's newest & most potent rockets, which burns a blend of hydrazine ("a common rocket fuel") & a related compound called unsymmetrical dimthyl hydrazine, or UDMH, & we were far from surprised to learn that this combustant will generate a mighty 530,000 pounds of thrust.
