题目

下列反应不属于氧化还原反应的是( ) A．2H2O22H2O ＋ O2↑ B．CuCl2＋2NaOH===Cu(OH)2↓＋2NaCl C．2Na＋2H2O===2NaOH＋H2↑ D．2Na ＋ Cl22NaCl 答案：答案 B 解析 双氧水中氧元素化合价部分升高，部分降低，是氧化还原反应，A错误；该反应是复分解反应，没有元素化合价变化，不是氧化还原反应，B正确；反应中Na失去电子，氢元素化合价降低，是氧化还原反应，C错误；钠元素化合价升高，氯元素化合价降低，是氧化还原反应，D错误。A few minutes before six o’clock, Mr. Smith left the house. He just wanted to 　　 the car when a gunman (持枪者) jumped up from the back seat. He 　　 a gun to Mr. Smith’s head. “Drive me to Paris!” he shouted.　　“All right,” Mr. Smith answered. He started the engine (发动机), pulled away (开走) from the side of the street and 　  down. Being 81 years old, he knew he could not fight with the gunman. He knew he needed help . Where were the police？ As he drove 　  each crossing, he looked up and down the side streets, hoping to find a police car, but he could see 　   . “Just my luck,” he thought. “If I were driving too 　, there would be a police car on every corner.” 　　Suddenly he pushed his foot down on the accelerator (加速器), and the car went   faster. “What are you doing？” shouted the gunman. “To 　   the police,” Mr. Smith answered. “I thought I saw a police car near there.”　　He ran red lights, drove wrong on one-way streets. On the two-way streets, he drove on the wrong side of the road. None of the policemen saw him. Again, Mr. Smith’s plan was not working. He had to try a new plan. 　　He turned at a corner and saw the 　  in front. Then he drove his car as fast as he could towards the police gate. The car knocked a police motorbike over and stopped. Mr. Smith shouted, “Help! Help!” Then he 　  back to grab (抓住) the man’s gun. At the same time the policemen heard the noise and quickly caught the gunman.小题1:A．stopB．beginC．leave　　D．start小题2:A．broughtB．pointedC．held 　　D．carried小题3:A．droveB．leftC．tookD．pushed小题4:A．pastB．overC．throughD．towards小题5:A．somebodyB．anybodyC．everybodyD．nobody小题6:A．fastB．slowlyC．generally　D．commonly小题7:A．moreB．muchC．veryD．quite小题8:A．look forB．keep away fromC．look atD．care about小题9:A．train stationB．police stationC．hospitalD．bank小题10:A．gotB．lookedC．turnedD．came