This is the question:
Now, I've gotten as far as this:
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Don't know if it's right or wrong, but solve and post all the steps..
This is the question:
Now, I've gotten as far as this:
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Don't know if it's right or wrong, but solve and post all the steps..
Not all the equations show up... =/
But I suppose that's what are given and this is how I work them out:
You are already given $\displaystyle \Delta H_1$ which is -91.8\ kJ/mol. (and this I think is the enthalpy of reaction and not formation and hence, you do not divide by 2)
Then, $\displaystyle \Delta H_2 = (3\times -241.8)\ kJ/mol$ (since you have 3 mol of water being formed from my Hess Cycle)
Then, $\displaystyle \Delta H_3 = (2\times -906.2)\ kJ/mol$ (I think they gave you the standard enthalpy of combustion of ammonia. So, for each mol of ammonia burnt, you get 906.2 kJ but since you burn 2 moles, it's twice)
Then, $\displaystyle \Delta H_4 = ? kJ/mol$ This is what you need to find I think.
Then, from Hess' Law, we find that by following the arrows:
$\displaystyle \Delta H_2 + \Delta H_4 = \Delta H_1 + \Delta H_3$
This will give you the answer.