Answer:
-105 kJ
Explanation:
The enthalpy change of a reaction is the sum of the energy of the bonds of the reactants and the products. The bonds at the reactants are being broken, so it's an endothermic reaction, so the bond energy must be positive.
The bonds at the products are being formed, so the process is exothermic, and the bond energy must be negative. There are being broken 1 N≡N bond and 3 H-H bonds, and are being formed 6 N-H bonds:
Reactants: 945 + 3*432 = 2241 kJ
Products: 6*(-391) = -2346 kJ
ΔH = 2241 - 2346
ΔH = -105 kJ
Answer
A *single covalent bond* is formed by sharing one pair of valence electrons.They are less reactive comparatviely and have a high bond length
A *double covalent bond* is formed by sharing two pairs of valence electrons.They are moderately reactive and have moderate bond length.
A *triple covalent bond* is formed by sharing three pairs of valence electrons.They are highly reactive and have a low bond length.
