在含有 Cl-、Br-、I-的强酸性混合液中,若要使 Br-、I-氧化成Br2和 I2,而不使 Cl-氧化,应选用的试剂是( ) A.KMnO4 B.浓H2SO4 C.MnO2 D.KCl 答案:B解析:依据氧化还原反应规律,选择氧化性比Br2、I2强而比Cl2弱的物质。The more ______ people drive, the ______ traffic accidents there ill be.
[ ]A. careful; less B. careful; fewer C. carefully; fewer D. carefully; more