搜题请搜索小程序“爱下问搜题”
问题 选择题

一定温度下，在1L的密闭容器中发生可逆反应：N2（g）+3H2（g） 2NH3（g），达到平衡的标志是

A．NH3的生成速率与H2的生成速率相等

B．混合气体的密度不再发生变化

C．N2、H2、NH3的分子数之比为1∶3∶2

D．N2的转化率不再发生改变

答案

答案：D

阅读理解
阅读理解。

A: Look at the picture.
B: Oh, it's a picture of a classroom.
A: What are these?
B: They are chairs.
A: What are those?
B: They are desks.
A: Can you see two oranges?
B: Yes, I can. They are on a desk.
A. Where's Lucy's hat?
B: It's on her desk.
A: Is Lucy's bag behind her chair?
B: Yes, it is.
A: Are Lucy's books on her desk?
B: No. They are on the floor.
A: Can you see Lucy's pencils?
B: No, I can't.
A: What is that under her chair?
B. I think it is a hat.
A: No, it isn't. It's a cat.

1. This is a picture of  ____ .     
A. a classroom
B. a home          
C. a bedroom  
D. a school
2. These are  ____ . Those are ____ .
A. chairs; desks
B. desks ; desks    
C. chairs; chairs
D. desks; chairs
3.    ___are    ___a desk.  
A. An orange;on
B.Two oranges;at  
C Two oranges;on
D.Two apples;at
4. Lucy's bag is  ___  her chair. 
A. on        
B. behind        
C. in          
D. under
5. A    ___is under her chair.   
A. hat  
B. cup    
C. cake    
D. cat
查看答案
判断题

八五式消防战斗服适用于近火作业和抢险救援。
查看答案