【简答题】以邻二氮菲光度法测定Fe(
II ),称取样品0.500g,经处理后,加入显色剂,最后定容为50.0mL,用 1.0 cm的吸收池,在510nm波长处测得吸光度A=0.430。计算样品中铁的质量分数。当溶液稀释1倍后,其百分投射率将是多少?(摩尔吸收系数1.1X104L• mol-1. cm-1 )
【单选题】What does the word 'utilitarianism' (Para 4 Line 2) mean in the context?
【判断题】新古典主义的设计风格是经过改良的古典主义风格
【单选题】文章中提到, 法国学校必读的经典是以下哪位作家的作品?
【单选题】( )的设计风格是古典主义风格在现代社会的新的表现形式。
【简答题】以邻二氮菲光度法测定 Fe( II ), 称取样品 0.500g, 经处理后 , 加入显色剂 , 最后定容为 50.0mL 。用 1.0cm 的吸收池 , 在 510mm 波长下测得吸光度 A=0.430 。计算样品中铁的质量分数 ; 当溶液稀释 1 倍后其透射比将是多少 ?(xs10=1.1×104L·mol -1 .cm -1)
【单选题】What does "confront" mean in the sentence? We are learning how to confront death.
A.
to be faced with a problem
B.
to face up to and deal with a problem
C.
to meet sb. or sth. face to face with hostile
D.
to force sb. to face or consider a situation with evidence
【单选题】听力原文:W: I really want to know why Nancy is always so hostile toward me. M: Did you ever think of just coming right out and asking her? Q: What does the man think the woman should do? (14)
B.
Ask Nancy to come out.
C.
Talk to Nancy herself.