We tried to find a table for seven, but they were all ______. A. given away B. kept away C. taken up D. used up 答案:C某学生为了将氯化钠和氯化钙两种固体混合物分离,设计了下列实验方案:试回答下列问题:(1)加入过量Na2CO3溶液的目的是______.(2)B物质是______(填化学式).(3)在上述滤液中含有______和______溶质,在第⑤步蒸发之前应在滤液中加入过量的盐酸溶液,请写出有关的化学方程式:______.