Question

hey guys...plz solve the following problem.... it's urgent...I have exam tomorrow...​

Answer 1

N2(g) + 3H2(g) ------> 2NH3(g) ;

∆rH° = -92.4 KJ/mol

enthalpy of formation of NH3 means heat released in the formation of 1 mole of NH3 .

Here it is 2 moles

so, divide both sides by 2 in above reaction

1/2N2(g) + 3/2H2(g) ---> NH3(g) ;

Therefore , ∆fH° = ∆rH°/2 = -92.4/2 = 46.2 KJ/mol

Hope you understand.

All the very best for your Exam.