题目

下列事实一定能说明HF是弱酸的是（  ） ①常温下NaF溶液的pH大于7；  ②用HF溶液做导电性实验，灯泡很暗；    ③HF与NaCl不能发生反应；④常温下0.1mol/L的HF溶液的pH为2.3；   ⑤HF能与Na2CO3溶液反应，产生CO2气体；  ⑥HF与水能以任意比混溶；   ⑦1mol/L的HF水溶液能使紫色石蕊试液变红。A．①②⑦   B．②③⑤ C．③④⑥      D．①④ C根据短文内容及首字母提示，填写所缺单词，使短文意思完整，每空限一词。(15分)   Former Prime Minister Margaret ThatcherC英国前首相玛格丽特•撒切尔) p 1 away at the age of 87 o 2 the morning of April 8 ,2013. Her son and daughter confirmed the news later that day. People from different countries mourned the 1 3 of a great leader.   Thatcher,a grocer’s (杂货商) daughter,was born in Lincolnshire. She received e 4 at the local grammar school. L 5,she became a top student of University of Oxford and was involved in politics (政治) there. Thatcher was the leader of Britain from 1975 to 1990. In 1976,when Thatcher visited Russia,a Russian newspaper c 6 her “the Iron Lady” for her personal and political toughness. Since then ,丁hatcher has been k 7 as the Iron Lady all over the world. Thatcher thought the title gave h 8 much personal pleasure.   Thatcher was the first woman prime minister of Britain. She was also c 9 as a great prime minister. To many Englishmen,Thatcher not only led the country,but also saved the country. She put her effort into developing Britain’s economy and made Britain be a formidable (令人畏惧的) rival (竞争者) on the international stage.   Thatcher was a great politician. Her excellent characteristics will always be remembered by those who worked c 10 with her. And she will be in our memory and in history forever.1.p      2. o      3. 1     4. e     5. L   6.c      7. k      8. h     9. c     10. c