问题 问答题 简答题

用元素符号及数字表示物质分子组成的化学式叫做分子式,如苯的分子式为“C6H6”,它包含了那四方面意义?

答案

参考答案:

1.代表苯的一个分子;

2.显示了组成苯分子的元素品种和数量;

3.可计算出分子量;

4.组成苯的碳原子和氢原子的相互比例。

完形填空
完形填空。
     One evening after dinner, Mr. and Mrs. Bond called a family meeting."We've to make a __
decision,"Mr. Bond announced."You see, your mother has been offered a post as codirector of a
TV station in Chicago._2_,the station is not here. After _3_ long and hard about it, we've _ that
the right decision is to move to Chicago."
     Marc looked _5_, while his sister Rachel breathlessly started asking when they'd be moving."It's
surprising, but exciting," she said.Marc simply said," I can't leave my _6_. I'd rather stay here and live
with Tommy Lyons!"
     The Bonds hoped that by the time they moved to Chicago in August, Marc would grow more _7_
  the idea of leaving. However, he showed no  _ 8    of accepting the decision, refusing to __9_ his
belongings.
     On the morning of their move, Marc was nowhere to be _10_. His parents called Tommy Lyons'
house, but Mrs. Lyons said she hadn't seen Marc. Mrs. Bond became increasingly _11_ while her
husband felt angry with their son for behaving so _12_.
     What they didn't know was that Marc had started to walk up to Tommy's house with a faint idea
of __13__ in the Lyons' attic (阁楼) for a few days. However, as he walked along all the _14_
landscape of his neighborhood _15_ him of the things he and his family had done together: the green
fence he and his mother had painted; the trees he and his sister used to _16_ while playing hideandseek;
the park _17_ he and his father often took walks together. How much would these _18_ without his
family, who made them special in the first place? Marc didn't spend _19_ answering that question but
instead, he hurried back to his house, _20_ if there were any boxes of the right size to hold his record
collection.
( )1.A.different  
( )2.A.Besides  
( )3.A.discussing  
( )4.A.known  
( )5.A.shocked  
( )6.A.classmates  
( )7.A.delighted at
( )8.A.ways  
( )9.A.pack  
( )10.A.observed  
( )11.A.anxious  
( )12.A.impatiently
( )13.A.hiding  
( )14.A.beautiful  
( )15.A.recalled  
( )16.A.plant  
( )17.A.which  
( )18.A.cost  
( )19.A.time  
( )20.A.looking  
B.Quick      
B.However    
B.Quarrelling
B.Recognized  
B.puzzled    
B.friends    
B.pleased with
B.signs      
B.collect    
B.watched    
B.angry      
B.irregularly
B.staying    
B.familiar    
B.remembered  
B.water      
B.where      
B.value      
B.courage    
B.wondering  
C.wise  
C.Therefore  
C.complaining  
C.concluded  
C.discouraged  
C.neighbours  
C.used to      
C.interests  
C.tie  
C.found  
C.frightened  
C.irresponsibly
C.sleeping  
C.splendid  
C.warned  
C.climb  
C.that  
C.mean  
C.strength  
C.asking  
D.final        
D.Anyhow      
D.thinking    
D.insisted    
D.excited      
D.parents      
D.worried about
D.hopes        
D.pile        
D.noticed      
D.miserable    
D.selflessly  
D.living      
D.modern      
D.reminded    
D.hide        
D.what        
D.measure      
D.patience    
D.expecting    
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