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In chemistry, a strong electrolyte is a solute that completely, or almost completely, ionizes or dissociates in a solution. These ions are good conductors of electric current in the solution. Originally, a "strong electrolyte" was defined as a chemical compound that, when in aqueous solution , is a good conductor of electricity.
In chemistry, an electrophile is a chemical species that forms bonds with nucleophiles by accepting an electron pair. [1] Because electrophiles accept electrons, they are Lewis acids . [ 2 ] Most electrophiles are positively charged , have an atom that carries a partial positive charge, or have an atom that does not have an octet of electrons.
It is usually much less important than chemical weathering, but can be significant in subarctic or alpine environments. [5] Furthermore, chemical and physical weathering often go hand in hand. For example, cracks extended by physical weathering will increase the surface area exposed to chemical action, thus amplifying the rate of disintegration ...
Because they form a strong electrophile when treated with Lewis acids, acyl halides are commonly used as acylating agents. For example, Friedel–Crafts acylation uses acetyl chloride (CH 3 COCl) as the agent and aluminum chloride (AlCl 3) as a catalyst to add an acetyl group to benzene: [2] Friedel-Crafts acylation of benzene by ethanoyl chloride
Case hardening is a weathering phenomenon of rock surface induration.It is observed commonly in: felsic alkaline rocks, such as nepheline syenite, phonolite and trachyte; pyroclastic rocks, as pyroclastic flow deposit, fine air-fall deposits and vent-filling pyroclastic deposits; sedimentary rocks, as sandstone and mudstone.
In these reactions, the conjugate acid of the carbonyl group is a better electrophile than the neutral carbonyl group itself. Depending on the chemical species that act as the acid or base, catalytic mechanisms can be classified as either specific catalysis and general catalysis. Many enzymes operate by general catalysis.
The effect can be classified into two types, namely the +E effect and the -E effect. This classification is based on the direction of electron pair transfer. When the attacking reagent is electrophile, the +E effect is generally observed and π-electrons are transferred to the positively charged atom.
For example, compared to benzene, pyrrole is more rapidly attacked by electrophiles. Pyrrole is therefore considered to be an electron-rich aromatic ring. [ 5 ] Similarly, benzene derivatives with electron-donating groups (EDGs) are attacked by electrophiles faster than in benzene. [ 6 ]