题目

根据下列实验装置图，回答有关问题。 ⑴ 图中标有①的仪器名称是     ▲     。 ⑵ 实验室制取氢气应选择的发生装置是     ▲  ，反应的方程式为        ▲      ，为若要获得较纯净的氢气，应选择的收集装置是     ▲   。为保证安全，点燃氢气前，应进行的操作是       ▲         。 ⑶ 实验室利用过氧化氢溶液和二氧化锰制氧气，反应的化学方程式为     ▲      。 若用B装置作制氧气的发生装置，应进行的改进是 �Mark was walking home from school one day when he noticed a boy ahead of him had dropped all of the books he was carrying. Mark helped the boy pick them up.   16  they were going the same way, he carried them for the boy. As they walked, Mark knew the boy’s name was Bill. Mark   17  discovered that he loved computer games, baseball and history and that he was having a lot of   18  with his other subjects.They arrived at Bill’s home first and Mark was invited in   19  Coke and to watch some television. The afternoon passed   20  with a few laughs and some shared small talk, and then Mark went home. They   21  to see each other around school, had lunch together once or twice and then   22  ended up from the same high school. Just three weeks before they finished school, Bill asked Mark if they could have a talk.Bill   23  him of the day years ago when they had first met. ‘Do you   24  wonder why I was carrying so many things home that day?’ asked Bill. ‘You see, I   25  out my locker because I didn’t want to leave a mess for anyone else. I had planned to   26  from home and I was going home to pack my things. But after we spent some time together   27  and laughing, I realized that   28  I had done that, I would have   29  a new friend and missed all the fun we would have together. So you see, Mark, when you picked up my books that day, you did a lot more. You   30  my life.’小题1:A．AfterB．SinceC．AlthoughD．Until小题2:A．alsoB．stillC．alwaysD．almost小题3:A．questionsB．ideasC．troubleD．doubt小题4:A．fromB．withC．toD．for小题5:A．quicklyB．proudlyC．freelyD．pleasantly小题6:A．continuedB．hopedC．preferredD．offered小题7:A．allB．bothC．everyD．none小题8:A．removedB．remindedC．askedD．described小题9:A．everB．soonC．evenD．never小题10:A．checkedB．tookC．cleanedD．put小题11:A．run awayB．take awayC．put awayD．pass away小题12:A．readingB．playingC．talkingD．watching小题13:A．beforeB．ifC．whileD．as小题14:A．forgottenB．madeC．becameD．lost小题15:A．helpedB．savedC．changedD．improved