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Corrosion
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Re: Corrosion
Hi,
Did you read Scibuddies explanation of pH and how it relates to acids and bases (https://www.sciencebuddies.org/science- ... cale.shtml)? I think that would help you understand the reaction better. Corrosion of steel (iron) is a chemical reaction but it is different in acids and bases and also with oxygen.
For example, putting steel wool into dilute hydrochloric acid produces a solution of iron (ferric) chloride and bubbles of hydrogen gas (flammable!). Putting it into dilute nitric acid gives ferric nitrate and hydrogen.
http://sciencepark.etacude.com/lzone/reactivity/Fe.php
Reaction of metallic iron (steel is just iron with some carbon 'dissolved' in it) with a base such as sodium hydroxide (NaOH) does not occur very readily. Ferrous or ferric IONS will react with the hydroxide ions of NaOH in solution, but not as metal.
The most important form of iron corrosion is from oxygen which produces iron oxide--rust (https://en.wikipedia.org/wiki/Rust). This is an oxidation reaction, however, with electrons being removed from iron by oxygen to produce ferric oxide (http://www.gewater.com/handbook/boiler_ ... ensate.jsp). The presence of water and dilute acids such as carbonic, from dissolved carbon dioxide, can speed up the corrosion of iron.
So, to answer your question, acids are much more likely to promote steel corrosion than bases.
I hope this helps. If you have more questions, let us know.
Sybee
Did you read Scibuddies explanation of pH and how it relates to acids and bases (https://www.sciencebuddies.org/science- ... cale.shtml)? I think that would help you understand the reaction better. Corrosion of steel (iron) is a chemical reaction but it is different in acids and bases and also with oxygen.
For example, putting steel wool into dilute hydrochloric acid produces a solution of iron (ferric) chloride and bubbles of hydrogen gas (flammable!). Putting it into dilute nitric acid gives ferric nitrate and hydrogen.
http://sciencepark.etacude.com/lzone/reactivity/Fe.php
Reaction of metallic iron (steel is just iron with some carbon 'dissolved' in it) with a base such as sodium hydroxide (NaOH) does not occur very readily. Ferrous or ferric IONS will react with the hydroxide ions of NaOH in solution, but not as metal.
The most important form of iron corrosion is from oxygen which produces iron oxide--rust (https://en.wikipedia.org/wiki/Rust). This is an oxidation reaction, however, with electrons being removed from iron by oxygen to produce ferric oxide (http://www.gewater.com/handbook/boiler_ ... ensate.jsp). The presence of water and dilute acids such as carbonic, from dissolved carbon dioxide, can speed up the corrosion of iron.
So, to answer your question, acids are much more likely to promote steel corrosion than bases.
I hope this helps. If you have more questions, let us know.
Sybee