题目

Our company forbids ______, that is to say, we are not allowed ______here. A. to smoke; to smoke                     B. smoking; smoking C. smoking; to smoke                D. to smoke; smoking 答案：C常温下，下列各组离子在指定溶液中一定能大量共存的是 A．无色透明的溶液中：Cu2+、Fe3+、SO42-、OH- B．使酚酞变红色的溶液中：Na＋、K＋、CO32- 、NO3- C．含有大量Ba（NO3）2的溶液中：Mg2+、NH4+、SO42-、Cl- D．0. 1 mol·L-1AlCl3 溶液中： K＋、NH4＋、HCO3-、SO42-