在一定条件下，下列物质不能和二氧化硅反应的是( )
①焦炭 ②纯碱 ③碳酸钙 ④氢氟酸 ⑤硝酸 ⑥氢氧化钾 ⑦氧化钙 ⑧氮气
A．③⑤⑦⑧
B．⑤⑦⑧
C．⑤⑧
D．⑤
答案：C
根据课本知识解答，⑤硝酸、⑧氮气不能和二氧化硅反应，故选C。
题目分析：
点评：本题主要考查物质的分类、反应类型、物质的性质等方面的知识，题目难度不大，注重基础知识的学习。
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| What do Chinese college graduates have in common with ants? The recent 1 Ant Tribes about the life of some young people 2 flock (群集) to Beijing after 3 university,describes the graduates,like ants,as smart but 4 as individuals,drawing strength from living together in communities. The book,which is based 5 two years of interviews with about 600 low-income college graduates in Beijing, 6 in mid-September,about a month ahead of an announcement by the Ministry of Human Resources and Social Security that 74% of the 6.11 million new graduates from universities and colleges had been 7 by Sept.1. The book's chief editor,Lian Sir,tells that piece of statistic says 8 about the real situation for many of these graduates. "I am always 9 how many of these employed college graduates are leading a happy life," Lian said. "I hope this book could offer a window on these graduates,whose stories are 10 known." The setting of the book is several so-called "settlement villages for college students" in the outskirts (市郊) of Beijing,where a large 11 of college graduates 12 .Most of these graduates work for 13 or medium-sized businesses, 14 less than 2,000 Yuan a month. They live together because it's 15: The rent in these communities is only around 350 Yuan a month. Many of them travel several hours a day for short-term jobs or job interviews. Tangjialing,a small 16 20 kilometers from Tian'anmen Square,has around 3,000 17 villagers,but has become a 18 for more than 50,000 migrants (移民),most of whom 19 from universities or colleges all over the country. Lian describes the students' 20 as five or six-story buildings built by local farmers with 12 rooms on each floor and two or three people crammed (挤) together in each room of about 10 square meters. Up to 70 or 80 people share the same toilet and kitchen. | ||||
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