问题
选择题
已知H-H键能为436 KJ/mol,H-N键能为391KJ/mol,按化学方程式:N2 + 3H2 = 2NH3 ΔH=-92.4 KJ/mol,则N≡N键的键能是[ ]
A.431 KJ/mol
B.946 KJ/mol
C.649 KJ/mol
D.869 KJ/mol
答案
答案:B
已知H-H键能为436 KJ/mol,H-N键能为391KJ/mol,按化学方程式:N2 + 3H2 = 2NH3 ΔH=-92.4 KJ/mol,则N≡N键的键能是[ ]
A.431 KJ/mol
B.946 KJ/mol
C.649 KJ/mol
D.869 KJ/mol
答案:B