The standard enthalpy of formation of NH3 is - 46.0 kj/ mol. If the enthalpy of formation of H2 from its atoms is 6 kj/mol and that of N2 is - 712 kj/ mol, the average bond enthalpy of N — H bond in NH3 is :

Question

The standard enthalpy of formation of NH3 is - 46.0 kj/ mol. If the enthalpy of formation of H2 from its atoms is 6 kj/mol and that of N2 is - 712 kj/ mol, the average bond enthalpy of N — H bond in NH3 is : (A) -1102 kJ/mol (B) -964 kJ/mol (C) +352 kJ/mol (D) +1056 kJ/mol

Tardigrade Admin · Accepted Answer

Correct answer is (c) +352 kJ/mol

Q. The standard enthalpy of formation of NH3​ is −46.0kj/mol. If the enthalpy of formation of H2​ from its atoms is 6kj/mol and that of N2​ is −712kj/mol, the average bond enthalpy of N—H bond in NH3​ is :

-1102 kJ/mol

-964 kJ/mol

+352 kJ/mol

+1056 kJ/mol

Correct answer is (c) +352 kJ/mol

Q. The standard enthalpy of formation of $N H_{3}$ is $- 46.0 kj / m o l$ . If the enthalpy of formation of $H_{2}$ from its atoms is $6 kj / m o l$ and that of $N_{2}$ is $- 712 kj / m o l$ , the average bond enthalpy of $N — H$ bond in $N H_{3}$ is :