问题
选择题
Look! Some women are chatting ______ over there and the rest _____ looking at the pictures.[ ]
A. happy, is
B. happily, is
C.happily, are
D. happy, is
答案
答案:C
Look! Some women are chatting ______ over there and the rest _____ looking at the pictures.[ ]
A. happy, is
B. happily, is
C.happily, are
D. happy, is
答案:C
(1)阅读、分析下列两个材料:材料一:
材料二:
物质 | 熔点/℃ | 沸点/℃ | 密度/g•cm3 | 溶解性 |
乙二醇(C2H6O2) | -11.5 | 198 | 1.11 | 易溶于水和乙醇 |
丙三醇(C3H8O3) | 17.9 | 290 | 1.26 | 能跟水、酒精以任意以互溶 |
A.蒸馏法 B.萃取法C.“溶解、结晶、过滤”的方法D.分液法
①将纯碱从氯化钠和纯碱的混合物中分离出来,最好应用______;
②将乙二醇和丙三醇相互分离的最佳方法是______.
(2)阅读材料三:在溶解性方面,Br2(溴)与I2很相似,其稀的水溶液显黄色.在实验室里从溴水(Br2的水溶液)中提取Br2和提取I2的方法相似.回答下列问题:
①常用的提取方法是______,化学试剂是______,最主要的仪器是______.
②若观察发现提取Br2以后的水还有颜色,解决该问题的方法是______.