A:FeCl3溶液(FeCl2):通入适量Cl2
B:CO(CO2):通过NaOH溶液洗气后干燥
C:MnO2(KCl):加水溶解后过滤、洗涤、烘干
D:SO2(HCl):通过饱和Na2CO3溶液洗气后干燥
一个球,圆溜溜,雨天无,晴天有。早从东方起,晚在西山落。____
When she knew her son was out of danger, she was relaxed.