题干

某现代化的自动酸度测定仪有自动校正温度的功能,能把不同温度下测得的pH自动校正为常温下的数据,下列说法正确的是                                   (  )

A:用该仪器测定碳酸饮料,pH等于7

B:无论什么温度,该仪器测定CH3COOH与CH3COONa的混合溶液,pH一定小于7

C:用该仪器测定某溶液pH等于6,该溶液在原温度下pH一定大于6

D:在80 ℃时,测定某溶液pH=7,若不校正,pH应小于7

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D

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完形填空

     When people think of tigers, they think: strong and dangerous. But now, the big animal is calling for our help.

     There were once eight kinds of   1   in the world, but three died out during the 20th century. In the last 70 years, the   2   of Siberian tigers (东北虎) has gone from as many as 300 to   3   22 somewhere. The Siberian tiger has been   4   dying out completely. If the government doesn't make any efforts, it's quite   5   that there will be no more Siberian tigers in China in ten to twenty years.

     In order to double the number of wild tigers in the   6   ten years, the World Wildlife Fund for Nature has started a program recently. It   7   save wild tigers and put an end to tiger hunting and killing. China, together with twelve other   8  , has joined in.

     Wild animals, such as red deer and wild pigs, are the main   9   of the tigers. The hunting of these animals is the greatest threat(威胁) to tigers. So the most important thing is   10   the animals that tigers eat. To protect the wild tigers, we need to call on more people to stop eating and hunting wild animals.

 1 A. pigs        B. tigers             C. deer              D. lions

 2 A. name       B. kind              C. number           D. type

 3 A. less than    B. more than        C. bigger than       D. larger than

 4A. in need of   B. in danger of      C. in front of  D. in spite of

 5 A. possible     B. impossible   C. necessary         D. unnecessary

 6 A. last        B. next             C. past             D. first

 7 A. aims to     B. used to           C. refuses to         D. aimed to

 8 A. cities        B. provinces          C. countries          D. places

 9 A. friends      B. food               C. members          D. relatives

 10 A. to sell     B. to kill           C. to save           D. to buy