题目

下列实验操作合理的是(     ) A.实验室制乙烯时,在酒精和浓硫酸的混合液中,放入几片碎瓷片,加热混合物,使液体温度迅速升到170 ℃B.实验室制取肥皂时,待植物油、乙醇和氢氧化钠溶液的混合物加热充分反应后,冷却,用纱布滤出固态物质C.验证溴乙烷水解产物时,将溴乙烷和氢氧化钠溶液混合,充分振荡溶液、静置,待液体分层后,滴加硝酸银溶液D.验证蔗糖水解产物时,在蔗糖溶液中加入几滴稀硫酸,水浴5 min,加入新制银氯溶液 第二节短文改错(共l0小题;每小题l.5分,满分l5分) 此题要求改正所给短文中的错误。对标有题号的每一行做出判断: 如无错误,该行右边横线上画一个勾(√); 如有错误(每行只有一个错误),则按下列情况改正: 此行多一个词:把多余的词用斜线(\)划掉,在该行右边横线上写出该词,并也用斜线 划掉。 此行缺一个词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词。 此行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。 注意:原行没有错的不要改。 Every year, students who are eager get home for the Chinese     76.         New Year, line up at railway station for hours. Then   77.         they got into a crowded train and dream of the home – cooked 78.         meals what they’ll enjoy once they arrive home. This, 79.         they say, make all the trouble of getting home worthwhile .       80.         Therefore, many of them come to find home is not exactly      81.         how they remember it. Live away from their parents has    82.        made them used to a new life of freedom – one that within       83.         hours of arriving some begin to miss. Endless houseworks  84.         and complaining parents are just a little of the things that   85.       
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