206k views
1 vote
What is the enthalpy change for this reaction?

What is the enthalpy change for this reaction?-example-1
User Readren
by
7.1k points

2 Answers

1 vote
boyy that question is too difficult 
User Dan Keezer
by
6.7k points
3 votes

Answer:


\Delta _rH=-906.04kJ/mol

Step-by-step explanation:

Hello,

In this case of thermochemistry, the first step is to know all the involved species' enthalpies of formation as shown below (extracted from the NIST database):


\Delta _fH_(NH_3)^((G))=-45.9kJ/mol\\ \Delta _fH_(O_2)^((G))=0kJ/mol\\\Delta _fH_(H_2O)^((G))=241.8kJ/mol\\\Delta _fH_(NO)^((G))=90.29kJ/mol

Now, for this particular chemical reaction and taking into account the involved stoichiometric coefficient, the feasible expression to compute the enthalpy change for that reaction is:


\Delta _rH=6\Delta _fH_(H_2O)^((G))+4\Delta _fH_(NO)^((G))-\Delta _fH_(NH_3)^((G))\\\Delta _rH=6(-241.8kJ/mol)+4(90.29kJ/mol)-4(-45.9kJ/mol)\\\Delta _rH=-906.04kJ/mol

Best regards.

User Srinivas B
by
6.6k points