adding two reactions together
Posted: Fri Jan 25, 2019 9:08 pm
by Valeria Viera 1B
Can anyone show me how to add to reactions together for Hess’s law? Or give an example?
Thank you!
Re: adding two reactions together
Posted: Fri Jan 25, 2019 10:00 pm
by Chris Freking 2G
From the lecture on 1/25/19:
N2(g) + O2(g) --> 2NO(g) (ΔHrxn = 180kJ)
2NO(g) + O2(g) --> 2NO2(g) (ΔHrxn = -112 kJ)
Adding the above reactions gives the net reaction:
N2(g) + 2O2(g) --> 2NO2(g) (Hnet = 68kJ)
Re: adding two reactions together
Posted: Sat Jan 26, 2019 1:31 pm
by Nicole Elhosni 2I
If you have trouble visualizing it, it is kind of like the transitive property in math. So if A-> B, and B->C, then A->C and you can add each reaction's change in enthalpy, A->B and B->C, to get the entire reactions change in enthalpy, so from A->C!