机动车辆在坡路上行驶应遵循()原则
A、曲线行驶上坡
B、下坡熄火滑行
C、下坡换低速档,配合脚制动
D、以上全部
参考答案:C
根据句意及首字母提示,完成下列单词。
1. They are in the same grade, but they are in d_________ classes.
2. Zhao Wei is very beautiful (漂亮的), because (因为) she has two b________ eyes.
3. Yellow and blue can become (变成) g_________.
4. My sister and I have different l_________.
5. Michael, here is a l_________ for you. It's from your teacher.
对于可逆反应N2(g)+3H2(g)2NH3(g)(正反应为放热反应),下列说法中正确的是( )。
A.达到平衡后加入N2,当重新达到平衡时,NH3的浓度比原平衡的大,H2的浓度比原平衡也大
B.达到平衡后,升高温度,既加快了正、逆反应的速率,又提高了NH3的产率
C.达到平衡后,缩小容器的体积,既有利于加快正、逆反应速率,又有利于提高氢气的转化率
D.加入催化剂可以缩短达到平衡的时间,是因为正反应速率增大了,逆反应速率减小