Enthaply change

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Clinicall

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If reaction 1 is 2(H2) --> 4H is -870 Kj/mol
And if reaction 2 is C + 4H --> CH4 is +794 Kj/mol

Then the Enthaply change for the reaction is -76 Kj/mol

But if it asks for the change of Enthaply to generate 2 moles of CH4, is it -152 Kj/mol (doubled) or is it still -76 Kj/mol. I thought it would be double, but an app that I'm using says that I'm wrong, can someone confirm this or if this app is screwing me.
 
Oops, yes you're right, thats what I meant, but it still said it would only be -76. Maybe I should ditch this app before it gives me too many other false answers. Thanks for confirming
 
If reaction 1 is 2(H2) --> 4H is -870 Kj/mol
And if reaction 2 is C + 4H --> CH4 is +794 Kj/mol

Then the Enthaply change for the reaction is -76 Kj/mol

But if it asks for the change of Enthaply to generate 2 moles of CH4, is it -152 Kj/mol (doubled) or is it still -76 Kj/mol. I thought it would be double, but an app that I'm using says that I'm wrong, can someone confirm this or if this app is screwing me.

Enthalpy is an extensive property... so yes it would be -152 KJ
 
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