4D.17

[405669838]

The question is "Use the data in Appendix 2A to calculate the standard reaction enthalpy for the reaction of pure nitric acid with hydrazine:
4HNO3+5N2H4=7N2+12H2O"

I thought I knew how to do it but then checked my answer and was wrong, and I am having a hard time following the solution. Thanks in advance!

[Natalie Keung 1D]

Hi!
For this question you just want to look at the chart and find the delta H for each of the compounds. Make sure to note if you're getting the right number for the state (solid, liquid, gas, aqueous) because it is different per each state. Once you find this, use the equation delta H= H of products- H of reactants.

It should be 12(Delta H of H20(l))-((4(delta H of HNO3(l)+5(delta H of N2H4)). The numbers in front of the delta H's are the stoichiometric coefficients from the balanced equation.

I hope this helps!