题目

乙醇的脱水反应:(1)写出本题中制备1,2-二溴乙烷的两个化学反应方程式._________________                _                                (2)安全瓶b可以防止倒吸,并可以检查实验进行时试管d是否发生堵塞．请写出发生堵塞时瓶b中的现象.________________   __       .(3)容器c中NaOH溶液的作用是:_______________________    __.(4)某学生在做此实验时,使用一定量的液溴,当溴全部褪色时,所消耗乙醇和浓硫酸混合液的量,比正常情况下超过许多.如果 假如你是英国的交流学生Neil，你在Sunshine Middle School两个月的学习生活即将结束。请你根据以下提示，用英语给Sunshine Middle School校长写一封感谢信。内容包括：what you’ve learned about Chinese culturehow the teachers and students help youwhat your homestay family do for you注意：1.词数90左右，可适当发挥。感谢信的开头和结尾已经给出，不计入总词数。2.文中不得提及有关考生个人身份的任何信息，如校名、人名等。Dear Sir,I would like to express my thanks to you. During my two-month stay in Sunshine School,_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________I feel really grateful for what you have done for me.Yours sincerely,Neil