help ! basic lab experiment gone awry !

[Spacegata]

Hi everyone. I am doing a beginner chemistry course from abroad.

I am in chile... and so I *think* I have found the right ingredients to complete my lab but my results are not what I expected. *the experiment is REALLY basic.....* Its a kitchen lab, where I was asked to put

 

an steel (iron) nail

a galvanized (zinc ) nail

a penny

and a nickel

 

in vinegar. (and watch the reaction.)

(There are no pennies in chile. and the only STEEL nail I could find was STAINLESS steel.)

 

so. I saw the zinc reaction > releasing H2 gas.

But the copper pipe, stainless steel nail and nickel (amazingly, I still had a canadian nickel in my purse ) didnt show any signs of reaction.

 

*HELP?*

 

I thought the iron would react more ? (but stainless steel.... because its STAINLESS - perhaps doesnt react ?)

 

I know this is VERY basic for most of you.... Im really REALLY new to this.

And puzzled. (and interesting in understanding !)

 

any help at all would be appreciated. !

 

thank you in advance

[woelen]

The results of your experiments do not surprise me. Although metals in theory should yield H2 on dissolving in acid, in practice those reactions can be VERY slow.

 

Nickel hardly will react. Even in concentrated hydrochloric acid it does not react quickly, although it does dissolve. Iron reactivity can be greatly reduced by adding small amounts of other metals (e.g. chromium, vanadium, nickel). Stainless steel is an example of that.

 

I have done experiments like this with many metals, and also in many acids, and only a few metals are really reactive.