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I don't know if $\ce{C}$ or $\ce{CuO}$ react with $\ce{H2SO4}$. Some sources say that: $$\ce{C + H2SO4 -> CO2 ^ + 2SO2 ^ + 2 H2O}$$ (It seems to be similar to $\ce{Cu}$ reactions with $\ce{H2SO4}$). Is the reaction possible? If the answer is yes, in what conditions does the reaction take place?

And I was pretty sure that $\ce{CuO + H2SO4 -> CuSO4 v + H2O}$

But my chemistry book says that none of the reactions is possible. I'm little bit confused, some help would be apreciated.

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Carbon reacts with sulfuric acid to produce carbon dioxide and sulfur dioxide gas along with water. Sulfuric acid should be a concentrated, heated solution.

$$\ce{C + 2H2SO4 ->[\Delta] CO2 + 2SO2 + 2H2O}$$

More insight about this reaction can be found here.

Copper(II) oxide, a black solid, and dilute sulfuric acid react to produce copper(II) sulfate, giving a characteristic blue colour to the solution. From this solution, blue copper(II) sulfate pentahydrate crystals may be obtained if desired.

$$\ce{CuO + H2SO4⟶CuSO4↓+H2O}$$

It is a general "insoluble metal oxide is reacted with a dilute acid to form a soluble salt" type of reaction. It is a standard class experiment.

More insight about this reaction can be found here.

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1) $\ce{H2SO4}$ can react with pure graphite powder/ash at elevated temperatures. It is a Redox-reaction between $\ce{C}$ reducing $\ce{S}$ while being oxidized. Typically adding hydrogen peroxide to $\ce{H2SO4}$is required to oxidize carbon which actually is the result of a new acid peroxysulfuric acid $\ce{H2SO5}$.

2) $\ce{CuO}$ can be dissolved with $\ce{H2SO4}$. You can as find some "proof" here, note that the product turns blueish in the end, which is the color of $\ce{CuSO4}$. On the German wikipedia entry the formula is even mentioned in the synthesis section.

Both reactions work only with concentrated acid and with heat because $\ce{CuO}$ and $\ce{C}$ are thermodynamically stable and a certain temperature is needed before the reactions become exergonic.

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    $\begingroup$ My lab coat is made of carbon ??? $\endgroup$ – NotEvans. Dec 28 '15 at 19:12
  • $\begingroup$ Partly, if yours is also made from cotton. $\endgroup$ – BeschBesch Dec 28 '15 at 19:17
  • $\begingroup$ @BeschBesch thanks! What about $\ce{CuO + AgNO3}$ is it possible? If not, please explain. $\endgroup$ – scummy Dec 28 '15 at 19:57
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    $\begingroup$ @BeschBesch Don't confuse people. Lab coats are not even partially made of elementary carbon (and in any case, carbon is not why they are vulnerable to $\ce{H2SO4}$), dissolving $\ce{CuO}$ requires neither heat nor concentrated acid, and $\ce{CuSO4}$ is not blue (though its hydrate is; however, with concentrated acid you won't get the hydrate). $\endgroup$ – Ivan Neretin Dec 28 '15 at 20:21

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