功能收敛止血、固精止带、制酸止痛、收湿敛疮的药物是
A.瓦楞子
B.牡蛎
C.乌贼骨
D.赤石脂
E.禹余粮
参考答案:C
解析:[解释] 乌贼骨能收敛止血、固精止带、制酸止痛、收湿敛疮。
化学反应N2+3H2 2NH3的能量变化如下图所示,该反应的热化学方程式是( )
A.N2(g)+3H2(g) 2NH3(l) ⊿H =2(a—b—c)kJ·mol-1
B.N2(g)+3H2(g) 2NH3(g) ⊿H =2(b—a)kJ·mol-1
C.1/2N2(g)+3/2H2(g) NH3(l)⊿H = (b+c—a)kJ·mol-1
D.1/2N2(g)+3/2H2(g) NH3(g)⊿H = (a+b)kJ·mol-1
求y"+2y’+y=2ex的通解.