题目

Salt in the soil has always made it impossible to grow crops. But that’s now changing. Famous agriculturalist （农学家）Yuan Longping said they would grow a special rice. They would turn 100 million mu of saline-alkali （盐碱的）land into farmland in the country over the next 10 years. In 2017, Yuan’s team successfully grew rice on the saline-alkali land in Jiangsu Province. It is called sea rice. Now they have made great progress. Both China and many other countries around the world have large saline-alkali land. If all of it can be used to grow rice and grain, it is very importⅠ、阅读、分析下列两个材料：物质熔点/℃沸点/℃密度/g?cm-3溶解性乙二醇C2H6O2-11.51981.11易溶于水和乙醇丙三醇C3H8O317.92901.26跟水、酒精以任意比互溶根据上述材料及课本知识，回答下列问题（每空只填一个字母选项，）：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 （3）用CCl4提取溴水中的溴单质的最佳方法是 （4）分离汽油和水的最佳方法是 Ⅱ、鉴别四种溶液：NH4Cl、（NH4）2SO4、NaCl、Na2SO4，若只用一种试剂，则该试剂可以是 ．（不能用焰色反应）