So electronegativity is the measure of the tendency of an element to attract electrons and electropositivity is the tendency of an element to lose electrons. And I think it can be related to corrosion. Many ways are designed to stop corrosion and one way is through a sacrificial anode or cathodic protection. Sacrificial anodes, such as zinc, have more negative(less positive) electrode potential compared to iron, making it easier to be oxidized.(or easily lose electrons which makes it less electronegative and more electropositive). Now I want to know how to make an element, such as copper, more electropositive, to the point that it is more electropositive than iron and can be used as a sacrificial anode.
Rendell, You should not forget that every metal has its natural energy called potential.
This is independent of electronegativity or electropositivity. If you take a look at the galvanic series table you will understand that the most reactive metal is magnesium which should have highest affinity for corrosion in accordance with the direction of your question, whereas Gold and Platinum comes last at the cathodic end indicating that if they must corrode, their corrosion rate will be extremely slow such that it may take several years to be noticed, except in aggressive acids or alkaline media. Conversely, Mg is not the most reactive metal just like Pt or Au are not the most noble in terms of electron loss.
Take a look at galvanized iron sheets, considering Zn and Fe which element would you consider more electropositive? Zn is more electropositive than Fe, so Zn should be corroded faster than Fe but it does not happen so, rather, Zn is used to galvanize Fe.
Therefore, electropositivity and electronegativity has nothing to do with sacrificial protection; corrosion current does not agree with electron loss/gain.
Thank you Dr. Anoop, that was a powerful encouragement for me. I am humbled with your recommendation.
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