问题
选择题
下列根据实验现象所得出的结论一定正确的是 [ ]
A.某无色溶液滴加酚酞试液后显红色，则该溶液显碱性
B.某无色溶液加入盐酸产生无色无味的气体，该溶液中一定含有大量的CO32-
C.某气体能使品红溶液褪色，则该气体为SO2气体
D.电解某无色液体得到H2和O2，测其体积比为2:1，则该液体为纯水
答案
答案：A
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下列根据实验现象所得出的结论一定正确的是 [ ]
A.某无色溶液滴加酚酞试液后显红色，则该溶液显碱性
B.某无色溶液加入盐酸产生无色无味的气体，该溶液中一定含有大量的CO32-
C.某气体能使品红溶液褪色，则该气体为SO2气体
D.电解某无色液体得到H2和O2，测其体积比为2:1，则该液体为纯水
答案：A
| 完形填空。 | |||
| Many people think the more time is spent, the more work will be done. So students have to spend the whole 1 doing schoolwork except the three meals. It is 2 to see students struggling (挣扎) in a sea of schoolwork both at school and at home. Modern students usually have many 3 . They love music and sports. They like reading and watching TV. A two-day weekend can get them 4 from too much schoolwork ,and they can do what they like. But still teachers do not think about it. They still arrange (安排) a lot of homework for students to do. 5 students have too much school work, they have no time to enjoy themselves. Students are really tired of their weekend homework. So they usually don't do their weekend homework 6 Sunday night. And there is not enough time for homework, students have to finish it 7 . The weekend homework makes teachers angry. Things always get 8 without right ideas. Too much schoolwork makes students lose interest in learning. It's also bad for their health. A horse runs faster after a 9 . So all the teachers should give students 10 pleasureand knowledge. | |||
| ( )1. A. day ( )2. A. never ( )3. A. books ( )4. A. busy ( )5. A. For ( )6. A. until ( )7. A. good ( )8. A. better ( )9. A. minute ( )10. A. either | B. morning B. common B. interests B. pleased B. With B. when B. poor B. afraid B. moment B. both | C. afternoon C. glad C. sports C. away C. Though C. at C. carelessly C. worse C. meal C. same | D. week D. hardly D. friends D. tired D. Because D. on D. happy D. wonderful D. rest D. between |