【简答题】欲测定含少量氯化钠的小苏打固态样品中NaHCO3的质量分数可采用以下四种方法。 方法四:不使用化学试剂,使用实验室常用仪器。 按要求回答下列问题: (1)方法一是将HCO3-离子转化为沉淀并称重,则试剂A为______________(填化学式)溶液;操作2包括_______________________。 (2)方法二操作1中要用到的玻璃仪器有烧杯、玻璃棒,还需要_______________...
【简答题】A.He was dropped from a class he really liked. B.The requirements for the class were ridiculous. C.The teacher refused to take into consideration his special condition. D.He could not carry out his pl...
【单选题】---- What did Father ask Lily yesterday? ---- Father asked her_______________.
B.
when did she pass the exam
C.
whether she had passed the exam
D.
how she has passed the exam
【简答题】关于正确处理人民内部矛盾的方针。指出,用( )的方法解决人民内部矛盾,这是一个总方针。
【判断题】健美操的首次国际比赛是由IAF在1981年举办的第一届国际健美操比赛.
【单选题】健美操的首次国际比赛是由IAF在()年举办的第一届国际健美操比赛.
【单选题】At that time, he spent as much time as he can _______the ancient status which would be sank in the river.