1.教材的系統性和科学性本章開始首先提出氮的性質,在氮的化学性質中指出了氮在普通情况下是不活潑的元素;但在一定的条件下它能和其他元素直接化合,並簡略地叙述了氮和氫、金属、氧作用後的生成物。在学生了解氮的化学性質的基础上,進一步重點地叙述了氮和氢的化合物——氨、銨盐,氮和氧的化合物——NO_2,NO,再由 1. Systematic and scientific teaching materials The chapter begins with the first proposition of the nature of nitrogen. It is pointed out in the chemical nature of nitrogen that nitrogen is an inactive element under ordinary conditions; however, under certain conditions it can be directly combined with other elements, And briefly describes the products of nitrogen and hydrogen, metals and oxygen. On the basis of students’ understanding of the chemical properties of nitrogen, further elaborated on the nitrogen and hydrogen compounds - ammonia, ammonium salts, nitrogen and oxygen compounds - NO 2, NO, and then by