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问题 选择题

下列四个图象，能正确反映其对应实验操作的是（　　）

A．加热高锰酸钾制氧气B．用等质量、等质量分数的过氧化氢溶液制取氧气C．向一定体积的稀盐酸中逐滴加入氢氧化钠溶液D．某温度下，向一定量饱和硝酸钾溶液中加入硝酸钾晶体
 

答案

答案：C

题目分析：A、实际上，高锰酸钾在加热的条件下分解方程式为2KMnO4K2MnO4+MnO2+O2↑．锰酸钾和二氧化锰都为固体，生成物中固体不会为零，即图象错误；故本选项不符合题意；B、用等质量、等浓度的双氧水制取氧气，产生氧气的质量相同，加入催化剂则反应速率大，不会出现氧气质量不同的情况，即图象错误；故本选项不符合题意；C、向一定体积的稀盐酸中逐滴加入氢氧化钠溶液，开始时溶液的pH小于7，恰好中和是pH等于7，氢氧化钠过量时溶液的pH大于7，图象正确，故本选项符合题意；D、某温度下，向一定量饱和硝酸钾溶液中加入硝酸钾晶体，溶质质量分数不会改变，图象错误，本选项不符合题意；

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Classified Advertisements
 If you need our service, please call 5161982.
                                                        For Rent
     Excellent Room for girls. Single, $115 a month. Double, $180 a month. Call 5160594.
     Family Home, 3 bedrooms, large yard. Call 3125766.
     Youth Paradise, room for boys, $100 per person. Call 8830553.
                                                         For Sale
     Coat for man, size 42, 1 year old, $85. After 6pm, Call 2125978
     Color TV, size 21, $150; Mp3 player, $45; Recorder, $25. Call 6963749
                                                      Help Wanted
     If you can find a few hours during the day to look after 2 school age children, please
call 3133694.
     A magazine needs a reporter. He or she should be good at writing in Chinese.
     Experience needed. Call 5201314.
                                                            Lost
     A yellow bag with a mobile phone and some books was left behind the library. Will the
finder come to Class l, Grade 3?
                                                           Found
     A black jacket was found on the playground yesterday afternoon (June, 21st). Will the
owner please ring 3655488?
1. If you want to make an advertisement, which number will you call?
A. 5160594.
B. 365588.
C. 5161982.
D. 313369.
2. Mary wants a room for herself, which room should she choose?
A. Family Home.
B. Double.
C. Single.
D. Youth Paradise.
3. The title "Classified Advertisements" probably means _____.
A. advertisements only for students to read
B. advertisements giving us useful information
C. advertisements that are very important
D. advertisements divided into different groups
4. If you want to find a part-time job, you will read _____.
A. Help Wanted
B. For Sale
C. For Rent
D. Lost
5. If a person has $115, he can buy _____.
A. TV and recorder
B. coat and recorder
C. coat and mp3 player
D. TV and mp3 player
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张彦远说：“图画者，所以鉴戒贤愚，（），若非穷玄妙于意表，安能合神变乎天机。”
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