题目

25 ℃时，将0.10 mol·L－1 CH3COOH溶液滴加到10mL 0.10mol·L－1NaOH溶液中，lg 与pH的关系如图所示，C点坐标是(6，1.7)。(已知：lg5=0.7)下列说法正确的是（） A . Ka(CH3COOH)＝5.0×10－5 B . Ka(CH3COOH)＝5.0×10－6 C . pH＝7时加入的醋酸溶液的体积小于10 mL D . B点存在c(Na＋)－c(CH3COO－)＝(10－6－10－8)mol·L－1 答案：A阅读下面短文并回答问题，然后将答案写到答题卡相应的位置上（请注意问题后的词数要求）。[1]A program in the United States brings scientists and engineers into elementary schools to teach teachers more about how to teach science.[2]Dave Weiss is a retired engineer. One day each week he volunteers at Georgian Forest Elementary School in Silver Spring, Maryland, near Washington. He, who is so enthusiastic and so much fun with the kids, works with teacher Fred Tenyke on science projects for ten years.[3]Student Jada Lockwood says she enjoys Mr. Weiss' visits to her classroom. She likes the drawings he uses to explain scientific ideas.[4]The American Association for the Advancement of Science sponsors the Senior Scientists and Engineers program. Dave Weiss has been a volunteer in that program for many years. The scientists and engineers help teachers in elementary schools improve their skills.[5]Mr. Weiss says he and the other volunteers help teachers by providing hands-on knowledge. He notes that science is an area in which many elementary school teachers have         _________experience. In elementary school, for the most part, a regular classroom teacher is responsible for teaching science, along with reading and math, and if they don't have a strong science background, just by nature, they're going to tend to underrepresent science in the curriculum.[6]American fifteen-year-olds scored about average in science among countries that took part in testing by the OECD in 2009. The OECD is the Organization for Economic Cooperation and Development.[7]Dave Weiss says he is concerned about such results, but hopeful for the future for American students learning science. Fred Tenkye thinks volunteers like Dave Weiss are helping students do that. "And if you can develop a passion for science, then eventually the grades and the test scores, then that will follow and increase, too." he said.小题1:How does Dave Weiss feel when he stays with students？(no more than 10 words)________________________________________________________________________小题2:What do the students think of Dave Weiss’s teaching？(no more than 6 words)________________________________________________________________________小题3:Fill in the blank in Paragraph 5 with proper words. (1 word)________________________________________________________________________小题4:What should the students do when they are learning science? (no more than 10 words)________________________________________________________________________小题5:What’s the main idea of this passage? (no more than 10 words) _______________________________________________________________________