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I was performing an experiment where I was supposed to construct a modified activity series between certain elements. I decided to use chlorides with the other metals for single replacement reactions so I could compare them all in relation to one another for my modified activity series.

When I placed about one gram of aluminum into about five milliliters of tin(IV) chloride, I was not able to see any reaction taking place. However, aluminum is higher in reactivity on the activity series so I know the aluminum had to react to replace the tin, but why would I not be able to see it?

Peter Mortensen
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Stevie Wonder
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    Did you activate the Al before adding it by etching the surface with acid? Al has a tenacious oxide surface layer that prevents it from reacting in many cases. – Waylander Apr 22 '17 at 17:48
  • This is what I was afraid the reason was. I did not now if it would lose that layer when added to the solution or not. If you make this an answer I will vote it up for rep. – Stevie Wonder Apr 22 '17 at 17:57

1 Answers1

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You need to activate the $\ce{Al}$ to remove the tenacious oxide layer that protects it from reaction. This can be done by a quick wash with dil $\ce{HCl}$, rinse with $\ce{EtOH}$ and finally $\ce{Et2O}$ before adding to the tin chloride.

Nilay Ghosh
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Waylander
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