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Reversible Endothermic and Exothermic Reactions

Do you remember what happens when you heat blue copper sulfate crystals?

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`stackrel blue{blue} {: "CuSO"_4".5H"_2"O" :} rarr stackrel "white" {: "CuSO"_4 :} + "5H"_2"O"`

To convert blue hydrated crystals into white anhydrous solid, heat is required. This reaction is endothermic.

Click here to review endothermic reactions.

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Now add the water produced to the white solid by clicking on the Start button.

The blue crystals are reformed and the thermometer shows that heat is given out in the process - exothermic.

`stackrel blue{"blue solid"} {: "CuSO"_4".5H"_2"O"_"(s)" :} stackrel "heat in" rarr stackrel "white solid" {: "CuSO"_"4(s)" :} + "5H"_2"O"_"(l)"`

`stackrel "white solid" {: "CuSO"_"4(s)" :} + "5H"_2"O"_"(l)" rarr stackrel blue{"blue solid"} {: "CuSO"_4".5H"_2"O"_"(s)" :} + "heat out"`

Click here to review exothermic reactions.

The process shown above is therefore a reversible reaction.

A reversible reaction is one which can be made to go in either direction by changing the conditions.

`"CuSO"_4".5H"_2"O"_"(s)" revarr "CuSO"_"4(s)" + "5H"_2"O"_"(l)"`

Click on the correct words to complete the sentence.

If the forward reaction is an ? process then the reverse reaction is an process.

Click on the appropriate option.  endothermic   exothermic

If you wish to use the standard data without answering the questions or carrying out the practical, press , or

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