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In chemistry, a reactivity series (or reactivity series of elements) is an empirical, calculated, and structurally analytical progression [1] of a series of metals, arranged by their "reactivity" from highest to lowest.
Electropositivity is a measure of an element's ability to donate electrons, and therefore form positive ions; thus, it is antipode to electronegativity. Mainly, this is an attribute of metals , meaning that, in general, the greater the metallic character of an element the greater the electropositivity.
The galvanic series (or electropotential series) determines the nobility of metals and semi-metals.When two metals are submerged in an electrolyte, while also electrically connected by some external conductor, the less noble (base) will experience galvanic corrosion.
Galvanic cells are extensions of spontaneous redox reactions, but have been merely designed to harness the energy produced from said reaction. [1] For example, when one immerses a strip of zinc metal (Zn) in an aqueous solution of copper sulfate (CuSO 4), dark-colored solid deposits will collect on the surface of the zinc metal and the blue ...
When two metals touch each other and water is present, electrolysis occurs. [2] One well known example is the reaction between zinc (Zn) and iron (Fe). Zinc atoms will lose electrons in preference to the iron as they are more electropositive and therefore zinc is oxidized and corrodes.
The electrolyte provides a means for ion migration whereby ions move to prevent charge build-up that would otherwise stop the reaction. If the electrolyte contains only metal ions that are not easily reduced (such as Na +, Ca 2+, K +, Mg 2+, or Zn 2+), the cathode reaction is the reduction of dissolved H + to H 2 or O 2 to OH −. [1] [2] [3] [4]
Zinc is a chemical element with the symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table .
The reaction can also be quenched with pyridine, which will scavenge ZnI 2 and excess reagents. [24] Methylation of heteroatoms is also observed in the Simmons–Smith reaction due to the electrophilicity of the zinc carbenoids. For example, the use of excess reagent for long reaction times almost always leads to the methylation of alcohols. [25]