【判断题】
[2]在以酚酞为指示剂、用NaOH为标准滴定溶液分析酸的含量时，近终点时应避免剧烈摇动
A. 对
B. 错
查看试卷，进入试卷练习
微信扫一扫，开始刷题
答案
A
解析
暂无解析
相关试题
【判断题】
[2]滴定至临近终点时加入半滴的操作是：将酸式滴定管的旋塞稍稍转动或碱式滴定管的乳胶管稍微松动，使半滴溶液悬于管口，将锥形瓶内壁与管口接触，使液滴流出，并用洗瓶以纯水冲下
A. 对
B. 错
【单选题】
[2]把反应Zn+Cu2→Zn2+ + Cu设计成原电池，电池符号为___。
A. （-）Zn|Zn2+|| Cu2+|Cu(+)
B. （-）Zn2+| Zn||Cu2+|Cu(+)
C. （-）Cu2+|Cu|Zn2+| Zn(+)
D. （-）Cu|Cu2+||Zn2+| Zn(+)
【单选题】
[2]用KMnO4法测定Fe2+，滴定必须在___。
A. c(H2SO4) =lmol／L介质中
B. 中性或弱酸性介质中
C. pH=10氨性缓冲溶液中
D. 强碱性介质中
【单选题】
[2]溴酸钾法测定苯酚的反应是如下：BrO3+ 5Br- +6H- =3Br2 +3H2O,C6 H5OH+ 3Br2 =C6H2Br3OH+3HBr, Br2 +2I- =I2+ 2Br- ,I2+ 2S2O2-3= S4O2-6+ 2I-，在此测定中，Na2 S2O3与苯酚的物质的量之比为___
A. 6：1
B. 3:1
C. 2：1
D. 1:1
【单选题】
[3]氧化还原反应的平衡常数K的大小取决于___的大小。
A. 氧化剂和还原剂两电对的条件电极电位差
B. 氧化剂和还原剂两电对的标准电极电位差
C. 反应进行的完全程度
D. 反应速率
【单选题】
[2]利用电极电位可判断氧化还原反应的性质，但它不能判别___。
A. 氧化还原反应速率
B. 氧化还原反应方向
C. 氧化还原能力大小
D. 氧化还原的完全程度
E. 氧化还原的次序
【单选题】
[1]已知(φΘAg+／Ag=0.7995V和AgI的Ksp=9.3×10-17。若在I-保持1.0mol／L溶液中，则上述电对的电极电位应是___。
A. -0.146V
B. 0.146V
C. 0.327V
D. -0.327V
【单选题】
[2]25。C时将铂丝插入Sn4+和Sn2+离子浓度分别为0.1mol/L和0.01mol/L的混合溶液中，电对的电极电势为___V。
A. φo(Sn4+/Sn2+)
B. φo(Sn4+/Sn2+)＋0.05916/2
C. φo(Sn4+/Sn2+)＋0.05916
D. φo(Sn4+/Sn2+)－0.05916/2
推荐试题
【判断题】
根据《河南省高速公路数字化视频监控设备联网技术要求》规定，信息采集采用的摄像头若为普通摄像头，其光圈性能应不低于F1.5；若为星光级摄像头，其光圈性能应不低于F1.8。
A. 对
B. 错
【判断题】
《河南省高速公路数字化视频监控设备联网技术要求》中规定的前端存储域一般由基层监控单元和其所辖外场监控设备中的存储设备组成；中心存储域一般存在于监控分中心或者省级联网监控中心。
A. 对
B. 错
【单选题】
河南省农村信用社手机银行中的无卡取款业务日累计限额（），每日可进行（）次无卡取款。___
A. 5000元，3次
B. 5000元，5次
C. 20000元，3次
D. 20000元，5次
【单选题】
— How are you, Bob?___
A. How are you?
B. I'm fine. Thank you.
C. How do you do?
D. Nice to meet you.
【单选题】
— Thanks for your help.___
A. My pleasure.
B. Never mind.
C. Quite right.
D. Don't thank me.
【单选题】
— Hello, my name is Charles Green, but ___ .
A. call my Charles
B. call me at
C. harles C. call me Charles
D. call Charles me
【单选题】
— ___, and how are you?
A. Don't mention it
B. Hm, not too bad
C. Thanks
D. Pretty fast
【单选题】
— I'm sorry. I am late due to the heavy traffic___
A. Well, it's OK.
B. No, it's all right.
C. You are welcome.
D. You are wrong.
【单选题】
— It's rather cold in here. Do you mind if I close the window?___
A. Yes, please.
B. No, please.
C. Sure, please.
D. I don't like it.
【单选题】
___He teaches physics in a school.
A. What does your father do?
B. Who is your father?
C. What is your father doing?
D. Where is your father now?
【单选题】
— Excuse me, how much is the jacket?___ It's 499 Yuan.
A. Oh, no. That's OK!
B. How do you like it?
C. Which do you prefer?
D. Would you like to try it on?
【单选题】
— Could you help me with my physics, please？___
A. No, no way.
B. No, I couldn't
C. No, I can't.
D. Sorry I can't. I have to go to a meeting right now.
【单选题】
— Could I speak to Don Watkins, please?___
A. Speaking, please.
B. Oh, how are you?
C. I'm listening.
D. I'm Don.
【单选题】
— Could I borrow your car for a few days?___
A. Yes, you may borrow.
B. Yes, go on.
C. Sure, here is the key. Enjoy your journey.
D. It doesn't matter.
【单选题】
— Thank you for inviting me.___
A. I really had a happy time.
B. Oh, it's too late.
C. Thank you for coming.
D. Oh, so slowly?
【单选题】
— May I see your tickets, please?___
A. Sure.
B. No, you can't.
C. No, they are mine.
D. Yes, you can.
【单选题】
— Please help yourself to the seafood.___
A. No, I can't.
B. Sorry, I can’t help.
C. Well, seafood don’t suit.
D. Well, I'm afraid I don't like seafood.
【单选题】
— Would you like to go to the concert with us this evening?___
A. No, I already have plans.
B. I'd love to, but I'm busy tonight
C. No, I really don't like being with you.
D. I'm ill, so I shouldn't go out.
【单选题】
— Congratulations! You won the first prize in today's speech contest.___
A. Yes, I beat the others.
B. No, no, I didn’t do it well.
C. Thank you.
D. It's a pleasure.
