题目

以下物质间的每步转化，不能通过一步反应实现的是                          （     ）    A.S→SO2→H2SO4→MgSO4                  B. Al→Al2O3→Al(OH)3→NaAlO2   C. Fe→FeCl2→Fe(OH)2→Fe(OH)3         D.N2→NO→NO2→HNO3       答案：B解析:略 3.根据首字母提示补全单词。1) Dr Bethune went on working t       the night.2) “Is this valuable painting m         for me?” This sentence means “Is the owner thinking of giving it to me”.3) Do you r      where you put the key,I can’t find it now.4) “More haste,less s       . ”This sentence means “Too much haste may result in delay”.5) The sign r       “Keep Left'