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问题 单项选择题

康熙瓷器的特点是（）

A、工整典雅

B、风格豪放

C、豪华繁缛

D、色彩绚烂

答案

参考答案：B

完形填空
完形填空。
    Ann is__1__English girl. She is fourteen. She is a__2__student. Her teacher is Miss White. Ann helps her teacher to put__3__books and ruler on the desk.
They have a new__4__. In it you can __5__40 desks and chairs. A blackboard, a clock and a map are__6__the wall.
    There are some pens on the desks. The red__7__is Ann’s, others are Kate’s. Kate is Ann’s __8__friend. Kate isn’t__9__here today. She is ill.
    Look at the clock. It’s about four o’clock. It’s time__10__to play games.
( )1. A. a            
( )2. A. middle school
( )3. A. my          
( )4. A. room        
( )5. A. look        
( )6. A. on          
( )7. A. pens        
( )8. A. fine        
( )9. A. /            
( )10. A. come         		B. an          
B. Middle School
B. your        
B. class        
B. look at      
B. in          
B. pencil      
B. good        
B. at          
B. to come      		C. the            
C. middle school’s
C. his            
C. grade          
C. see            
C. at              
C. one            
C. nice            
C. on              
C. go              		D. /              
D. Middle School’s
D. her            
D. classroom      
D. see at          
D. to              
D. ones            
D. right          
D. of              
D. to go          
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问答题

某实验小组以H2O2分解为例，研究浓度、催化剂、溶液酸碱性对反应速率的影响．在常温下按照如下方案完成实验．

实验编号反应物催化剂
①10mL2% H2O2溶液无
②10mL5% H2O2溶液无
③10mL5% H2O2溶液1mL0.1mol•L-1FeCl3溶液
④10mL5% H2O2溶液+少量HCl溶液1mL0.1mol•L-1FeCl3溶液
⑤10mL5% H2O2溶液+少量NaOH溶液1mL0.1mol•L-1FeCl3溶液
（1）催化剂能加快化学反应速率的原因是______．

（2）实验①和②的目的是______．实验时由于较长时间没有观察到明显现象而无法得出结论．资料显示，通常条件下H2O2稳定，不易分解．为了达到实验目的，你对原实验方案的改进是______．

（3）写出实验③的化学反应方程式______．

（4）实验③、④、⑤中，测得生成氧气的体积随时间变化的关系如图．分析上图能够得出的实验结论是______．
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