【单选题】已知反应2NH3=N2+3H2的标准平衡常数为0.25。同一条件下反应(1/2)N2+(3/2)H2=NH3的标准平衡常数为
【简答题】给下列的问句选择合适的答语。 ( ) 1. What are they doing? ( ) 2. How old are you? ( ) 3. What's the matter? ( ) 4. How are you? ( ) 5. Today is my birthday. A. Happy birthday. B. My head hurts. C...
【单选题】—I haven't seen Grace for a long time. —I haven't seen her, ________.
【单选题】They lost their way in the forest, and _____. Which of the following is wrong? [ ]
A.
what made matters worse was that night began to fall
B.
what was worse, it was getting dark
C.
to make matters worse that night was falling
D.
worse still, night had fallen
【单选题】It’s necessary to _________all the lights before you leave the classroom.
【简答题】A. strip off B. throw at C. throw away D. get off E. keep back F. make it G. straighten up H. take away I. with open arms J. fr...
【单选题】At the same time, after what you have said, I do not feel ______ in deciding on this matter entirely by myself.
【简答题】I. Complete the sentences with the correct form of the expressions in the box. A. tore up B. log on C. go about (sth.) D. on file E. not to mention ...
【单选题】函数在某点不可导,函数所表示的曲线在相应点的切线