题目

Beijing(Xinhua)------More than seven hundred students will serve for the 2008 Beijing Olympic Games not as volunteers but as interns(实习生), working for months before the event and during the Games to help ensure its success. A co-operation agreement was signed between the Beijing Organizing Committee for the Games of the XXIX Olympiad (GOCOG) and 16 Beijing-based universities and colleges. The schools will prepare the students to be interns. Although the interns will work without pay, they are considered different to volunteers, who will also provide services for the Games. Well-known sch下列根据实验操作和现象所得出的结论正确的是 选项 实验操作 实验现象 结论 A 向FeC12溶液中通入适量C12 溶液由浅绿 色变为黄色 C12的氧化性比FeC13的强 B 淀粉溶液在硫酸存在下水解一段时间后直接与银氨溶液混合 无银镜出现 淀粉没有水解 C 向澄清石灰水中通入某种气体 出现白色沉淀 该气体一定是CO2 D BaSO4固体加入饱和Na2CO3溶液中，过滤，向滤渣中加入盐酸 有气体生成