【单选题】—I don't like chicken ______meat, ______I like fish very much.
【单选题】为了除去混在 CO 2 中的 SO 2 和 O 2 ,下列试剂使用顺序正确的是 ( ) 1 饱和 Na 2 CO 3 溶 液 2 饱和 NaHCO 3 溶液 3 浓 H 2 SO 4 4 灼热铜网 5 生石灰
【单选题】汽水是CO 2 的饱和溶液,其中存在如下平衡: H 2 CO 3 H + +HCO 3 - ……① HCO 3 - H + +CO 3 2 - ……② 将汽水倒入试管中分别进行下列实验,相应分析结论错误的是
C.
加入CaCO 3 悬浊液,CaCO 3 的溶解平衡向正方向移动
D.
通入过量CO 2 或滴加氯水,溶液pH均减小
【单选题】蛋白质测定蒸馏过程中,接收瓶内的液体是( )。
【简答题】Passage 2 Dear Linda, I have been in England three months now. I hope you don't think I've forgotten you. There have been so many places to see and so many things to do that I've not had much time for...
【单选题】某温度下,向一未饱和的Na 2 CO 3 溶液中加入20g无水Na 2 CO 3 或加入50gNa 2 CO 3 ?7H 2 O晶体,都恰好使溶液达到饱和,则Na 2 CO 3 在此温度时的溶解度为( )
【简答题】英译汉:lubrication system
【简答题】在25℃,CO2气体压力等于1标准大气压时,CO2饱和水溶液中CO2的浓度约为0.034 mol.dm-3,计算溶液的pH和[CO32-]。通常把溶入的CO2都当成H2CO3,利用如下平衡式计算: H2CO3+H2O HCO3-+H3O+ Ka1=4.5×10-7
【单选题】听力原文:M: Would you like to go to see the movies with me this evening? W: I'd love to. But I’m just getting over the flu. What will the woman probably do this evening?
【单选题】I like comedies _______ I don't like documentaries at all; they're more than boring. [ ]