题目

下列有关比较中，大小顺序排列错误旳是（ ）A.热稳定性：H2O>HF>H2SB.分散系中分散质粒子旳直径：Fe(OH)3悬浊液>Fe(OH)3胶体>FeCl3溶液C.原子半径：Na＞Si＞O D.结合质子能力：OH−＞CH3COO−＞SO42− 答案：【答案】A【解析】A．O、F、S的非金属性强弱顺序为F＞O＞S，所以热稳定性：HF＞H2O＞H2S，故A错误；B．溶液中分散质粒子直径小于1nm，胶体的分散质粒子直径在1nm−100nm之间，悬浊液的分散质粒子直径大于100nm，所以分散系中分散质粒子的直径：Fe(OH)3悬浊液>Fe(OH)3胶体>FeCl3溶液，故B正确；C．Si、Na位- Tom is never late for work. Why is he absent today? - Something ______ to him. A. must happen 　　 　 　 　 B. should have happened C. could have happened 　 　 D. must have happened