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Urgent Feasible reaction?

I have revised delta G but am stuck on this question, it does not provide delta H or delta S values at all so how can I do it?

The following link is the question: http://img44.echo.cx/img44/4869/feasible9gi.jpg

Cheers
you are given the standard free energy change - if it's negative then the reaction is feasible.

According to Hess's law all equations can be added and subtracted to provide new equations provididng you do the same with deltaG.

So construct each of the 'answer' equations and find its deltaG value.

example

reduction of zinc oxide by magnesium would be
ZnO + Mg --> MgO + Zn

this equation can be 'constructed' by equation 1 (divided by 2) and then subtracting equation 3 (also divided by 2)

Mg + 1/2O2 ---> MgO [deltaG]
Zn + 1/2O2 --> ZnO [deltaG]
subtract 2 from 1

Mg - Zn ----> MgO - ZnO [deltaG]

rearrange

Mg + ZnO --> MgO + Zn [deltaG]

this reaction is feasible
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supreme
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charco
you are given the standard free energy change - if it's negative then the reaction is feasible.

According to Hess's law all equations can be added and subtracted to provide new equations provididng you do the same with deltaG.

So construct each of the 'answer' equations and find its deltaG value.

example

reduction of zinc oxide by magnesium would be
ZnO + Mg --> MgO + Zn

this equation can be 'constructed' by equation 1 (divided by 2) and then subtracting equation 3 (also divided by 2)

Mg + 1/2O2 ---> MgO [deltaG]
Zn + 1/2O2 --> ZnO [deltaG]
subtract 2 from 1

Mg - Zn ----> MgO - ZnO [deltaG]

rearrange

Mg + ZnO --> MgO + Zn [deltaG]

this reaction is feasible


Thanks, my teacher didn't understand :smile:

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