问题 选择题

设NA为阿伏加德罗常数的值,下列叙述正确的是  (     ) 

A.标准状况下, 22.4 L H2O含有分子数为NA

B.分子总数为NA的N2、CO混合气体体积约为22.4 L,质量为28 g

C.常温常压下,1.6 g CH4含原子数为0.5NA

D.足量的CO2与39 g Na2O2发生反应,转移的电子数为NA

答案

答案:C

题目分析:A、标准状况下,水是液态不是气态,错误;B、没有说在什么状况下,错误;C、正确;D、足量的CO2与39 g Na2O2发生反应,转移的电子数为0.5NA,错误。

补全对话,情景问答
从Ⅱ栏中找出与I栏相对应的答语。
I                                                          
( )1. Good afternoon.                         
( )2. What's this?                          
( )3. Who's your friend?                       
( )4. Sit down please.                     
( )5. Nice to meet you.                   
( )6. Goodbye!                           
( )7. Good evening.                        
( )8. How are you?                     
( )9. Spell“pen" ,please.                   
( )10. Sorry.            
II                                                                 
A. That's all right.                                             
B. Goodbye !                                                     
C. I'm  fine ,thanks.                                            
D. Mike is my friend.                                            
E. P-E-N.                                                        
F. Good aftemoon.                                                
G. Thank you.                                                    
H. Good evening.                                                 
I. It's an apple.                                                 
J. Nice to meet you,too.     
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