题目

--When will you come home for dinner? I will prepare it for you. --Don’t ______it. I’ll eat out with my friends.   A. care about   B. bother about   C. worry about   D. talk about 答案：B(14分)某同学设计右图所示的实验装置,进行一氧化碳还原氧化铜的实验。试回答: (l)该装置存在的一个主要问题是                                                ;你的改进方法是                                           .(2)实验开始时,是先                      ,后                               ；目的是                                                   .(3)实验结束时,是先                      ,后                               ；目的是                                                   .(4)实验过程中,图中A处能观察到的实验现象是                               ；发生反应的化学方程式为                                             。B处观察到的实验现象是                                                。发生反应的化学方程式为                                             。