【单选题】Where did the conversation take place?
【简答题】一粉红色固体的实验式为CoCl3·5NH3·H2O,其溶液也呈粉红色,用AgNO3溶液滴定时迅速生成3 mol AgCl沉淀。粉红色固体受热失去1 mol H2O,生成紫色固体,其中NH3:Cl:Co的比例不变。紫色固体溶解后,其溶液的摩尔电导值比粉红色溶液小,试推断粉红色和紫色两个八面体配合物的结构,并分别给以命名。
【单选题】Where did the conversation take place?
【单选题】Only when______ can the postal code system achieve its full efficiency.
A.
all the post offices in the country have the fight machines
B.
all the post offices have trained staff
C.
most post offices have the right machines
D.
most post offices have trained staff
【多选题】在工件的装夹中,直接找正安装的定位精度主要取决于()。
【单选题】—Excuse me, could you tell me where I can post a letter? —_________. Turn left. There is a post office on the Fifth Road. [ ]
【单选题】— Excuse me, can you tell me where the nearest bank is, please? — _____ Oh yes! It's past the post office, next to a big market. [ ]
B.
Oh, I beg your pardon?
【多选题】在工件的装夹中,直接找正安装的定位精度主要取决于()