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Science project: Hydrochloric acid affect on different metals

Hello, I'm a junior in high school. I'm doing a science fair project on the effect of hydrochloric acid on different types of metals. The metals I used for the experiment are Iron, Aluminum, steel, and copper. I have done it and I have seen the reactions. My problem is getting the equation and explaining what it going on in the reaction. Can someone please give me the equations for all the metals reacting with hydrochloric acid? And then explain what's going on? I would really appreciate it. The Final project is due in a few weeks and ii need to do the data and final finishing works. I would really appreciate it. Thank you =)

Hanan A
Student - Detroit, Michigan, United States
November 17, 2008

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November 18, 2008

Hi, Hanan. HCl is a simple mineral acid, not an oxidizing acid, so the reaction should be (if I didn't screw up x and y too much):

2HCl + M --> H² + M^2x/yCl_x

If the metal oxidizes to a valence state of +1, then x is one half and y is one. If valence state +2, then x is one and y is one, etc.

So you need to look up at what valence state metals dissolve into simple acids, because that is more empirical than determinable through basic chemistry rules. Iron and steel are really the same thing in terms of reactions with acid. You didn't say, but presumably you discovered that copper doesn't directly dissolve in hydrochloric acid? It needs an oxidant, but sometimes this can just be the air (you can dissolve copper oxides in hydrochloric acid).

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey