题型:问答题 I am really worried about his grades in the coming test because of the little use he ______ of his spare time before it.A.didB.tookC.gotD.made 查看答案
题型:问答题 已知反应H++NO3-+SO32-→SO42-+NO↑+H2O,在某盐溶液中滴加氯化钡溶液和稀硝酸,溶液中有白色沉淀,对该盐溶液的判断正确的是( )A.一定含有SO42-B.一定含有SO32-C.一定含有Ag+D.以上离子均有可能 查看答案