A:Such challenging is the task; take to
B:So challenging is the task; take o
C:How challenging is the task; take u
D:The task is such challenging; take i
电能的利用是人类进入文明社会的标志.发电机的发明,使得人类大规模用电成为可能,如图所示,能表示发电机工作原理的是( )
2NO(g)+2CO(g) ⇌催化剂 2CO2(g)+N2(g) △H=-akJ·mol-1(a>0)
如图示意图,请据图回答下列问题: