AC
28.—How much sugar did you put in my coffee? It tastes so bitter.
—I am sorry to say that there’s ________left.I’ve forgotten to buy ______on my way
home.
A.nothing;it
B.something;anything
C.none;some
D.no one;some
若对照实验说明有系统误差存在,则应设法找出产生系统误差的原因,并加以消除。通常消除化学分析过程中系统误差的方法有()
A.做空白实验消除试剂、蒸馏水及器皿引入的杂质所造成的系统误差
B.校准仪器以消除仪器不准所引起的系统误差
C.引用其它分析方法作校正
D.做加标回收试验