Kaplan Gchem question

[RCLEE]

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Can anyone tell me why Kaplan's answer choice is correct. It's actually missing a mole of water. I calculated it and a a different answer but chose just anything random to look at their answer and explation. I spent like 10mins on this question, which was too much.

 

[FLOSS UR TEETH]

They are correct. Maybe you forgot your co-efficients?

2(-394)+2(-286)-(-1367)= +7

 

[wizi]

Can anyone tell me why Kaplan's answer choice is correct. It's actually missing a mole of water. I calculated it and a a different answer but chose just anything random to look at their answer and explation. I spent like 10mins on this question, which was too much.

how did you calculate it?

 

[RCLEE]

The balanced chemical equation required 3H2O(l). So one more more of water in liquid phase is needed. That means add -44 to the answer they have.

NVM. My bad, I see it. It's already in liquid form. 🙁. Thanks y'all!

 

[FLOSS UR TEETH]

The balanced chemical equation required 3H2O(l). So one more more of water in liquid phase is needed. That means add -44 to the answer they have.

I see what your saying.. I accidentally left out the water except I think it would be +44 because H2O(l) is on the products side so you would need to change the sign of the enthalpy of reaction giving 51 kJ as the answer.

Can anyone chime in?

 

[wizi]

I see what your saying.. I accidentally left out the water except I think it would be +44 because H2O(l) is on the products side so you would need to change the sign of the enthalpy of reaction giving 51 kJ as the answer.

Can anyone chime in?

lol you were right when you left out the first reaction 🙂

44kJ is not related here.