题目

已知VmLAl2（SO4）3溶液中含有agAl3+，取出V/4 mL溶液稀释到4VmL，则稀释后溶液中的物质的量浓度为（）。A.mol/L      B.mol/L      C.mol/L      D.mol/L 答案：C【试题分析】The little boy looked __________ at the __________ tiger.A. frightened; frightening B. frightening; frightenedC. frightened; frightened D. frightening; frightening