Oxidation and specific heat capacity

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Marcin H
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Homework Statement


If a metal is highly susceptible to oxidation, what effect might this have on calculating the quantity of heat transferred to a metal? Use specific examples.

Homework Equations


Q=mcΔT

The Attempt at a Solution


Would oxidation change the specific heat of the metal? Since you are adding one electron aren't you changing the material and therefore changing the specific heat? I haven't had chemistry in a while, so I'm not sure how oxidation would have an effect my calculations. Example would be iron and rust. Would the mass also change? or just the specific heat capacity?
 
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I believe that In the case of iron and rust, the mass would change because the oxidation of iron includes the formation of iron oxides which have more mass than iron by itself. Because iron oxides also have different specific heat capacities, I would assume that would change as well. In both situations however, with increased mass and at least in the case of iron rusting, increased specific heat capacity, the Q value is going to increase as well.
 
The question is pretty ambiguous. If the only thing that you observe is a change of the temperature of the heated (cooled) "metal" (an I use quotes, as once it is partially oxidized it is no longer a metal, but a mixture of a metal and an oxide), then yes - fact that it gets oxidized can be a source of an error. But if you measure somehow amount of heat supplied (say, by using a resistive heating element and controlling V/A) fact that the metal got oxidized doesn't matter - unless this time you want to think about "metal" as in "whatever the original sample was minus oxides created in the meantime".

Yes, this is nitpicking, but apparently question want you to delve into nitpicking details, so it should be precise. Otherwise you need mind reading to find out what the question author was really thinking.