相关试题
【判断题】
[3]灭火器内的药液密封严格,不须更换和检查
【判断题】
[2]使用灭火器扑救火灾时要对准火焰上部进行喷射
【判断题】
[3]用过的铬酸洗液应倒入废液缸,不能再次使用
【判断题】
[2]纯水制备的方法只有蒸馏法和离子交换法
【判断题】
[2]天平窒要经常敞开通风,以防室内过于潮湿
【判断题】
[2]铂坩埚与大多数试剂不反应,可用王水在铂坩埚里溶解样品
【判断题】
[2]为防止静电对仪器及人体本身造成伤害,在易燃易爆场所应该穿化纤类织物、胶鞋及绝缘底鞋
【判断题】
[2]当眼睛受到酸性灼伤时,最好的方法是立即用洗瓶的水流冲洗,然后用200g/l的硼酸溶液淋洗
【判断题】
[2]凡是优级纯的物质都可用于直接法配制标准溶液
【判断题】
[2]铂金制品在使用中,必须保持表面的光洁,若有斑点,用其他办法除不去时,可用最细的砂纸轻轻打磨
【单选题】
相对误差小于0.1%,最少应称取基准物___g。M(KHP)=204.2g/mol。
A. 0.41
B. 0.62
C. 0.82
D. 1
【单选题】
[2]测定某石灰石中的碳酸钙含量,得以下数据:79.58%、79.45%、79.47%、79.50%、79.62%、79.38%。其平均值的标准偏差为___。
A. 0.0009
B. 0.0011
C. 0.009
D. 0.0006
【单选题】
[2]测定煤中含硫量时,规定称样量为3g精确至0.lg,则下列表示结果中合理的是___。
A. 0.042%
B. 0.0420%
C. 0.04198%
D. 0.04%
【单选题】
[2]按Q检验法(当n=4时,Q0.90=0.76)删除逸出值,下列哪组数据中有逸出值应予以删除___。
A. 3.03,3.04,3.05,3.13
B. 97.50,98.50,99.00,99.50
C. 0.1042,0.1044,0.1045,
D. 0.2122,0.2126,0.2130,0.2134
【单选题】
[2]一个分析方法的准确度是反映该方法___的重要指标,它决定着分析结果的可靠性。
A. 系统误差
B. 随机误差
C. 标准偏差
D. 正确
【单选题】
[3]下述论述中正确的是___。
A. 方法误差属于系统误差
B. 系统误差包括操作失误
C. 系统误差呈现正态分布
D. 偶然误差具有单向性
【单选题】
[1]下列论述中正确的是___。
A. 准确度高一定需要精密度高
B. 分析测量的过失误差是不可避免的
C. 精密度高则系统误差一定小
D. 精密度高准确度一定高
【单选题】
[2]总体标准偏差的大小说明___。
A. 数据的分散程度
B. 数据与平均值的偏离程度
C. 数据的大小
D. 工序能力的大小
【单选题】
[2]测定某试样,五次结果的平均值为32.30%,S=0.13%,置信度为95%时(t=2.78),置信区间报告如下,其中合理的是___%。
A. 32.30±0.16
B. 32.30±0.162
C. 32.30±0.1616
D. 32.30±0.21
【单选题】
[1]下列电子天平精度最低的是___。
A. WDZK-1上皿天平(分度值0.1g)
B. QD-1型天平(分度值0.01g)
C. KIT数字式天平(分度值0.1mg)
D. MD200-1型天平(分度值l0mg)
【单选题】
[1]电子天平的显示器上无任何显示,可能产生的原因是___。
A. 无工作电压
B. 被承载物带静电
C. 天平未经调校
D. 室温及天平温度变化太大
【单选题】
[1]滴定分析中,若怀疑试剂在放置中失效可通过___的方法检验。
A. 仪器校正
B. 对照试验
C. 空白试验
D. 无合适方法
【单选题】
[1]检验方法是否可靠的办法是___。
A. 校正仪器
B. 测加标回收率
C. 增加测定的次数
D. 做空白试验
【单选题】
[2]系统误差的性质是___。
A. 随机产生
B. 具有单向性
C. 呈正态分布
D. 难以测定
【单选题】
[2]比较下列两组测定结果的精密度___。甲组:0.19%,0.19%,0.20%,0.21%,0.21%。乙组:0.18%,0.20%,0.20%,0.21%,0.22%。
A. 甲、乙两组相同
B. 甲组比乙组高
C. 乙组比甲组高
D. 无法判别
【单选题】
[2]分析铁矿石中铁含量。5次测定结果为37.40%、37.20%、37.50%、37.30%和37.25%。则测得结果的相对平均偏差为___%。
A. 2.9
B. 0.29
C. 0.15
D. 1.5
【单选题】
[3]某标准滴定溶液的浓度为0.5010mol/L,它的有效数字是___
【单选题】
[3]下列数字中有三位有效数字的是___。
A. 溶液的pH为4.30
B. 滴定管量取溶液的体积为5.40ml
C. 分析天平称量试样的质量为5.3200g
D. 移液管移取溶液25.00ml。
【单选题】
[1]在不加样品的情况下,用与测定样品同样的方法、步骤,进行的定量分析,称之为___。
A. 对照试验
B. 空白试验
C. 平行试验
D. 预试验
【单选题】
[1]在进行离子鉴定时未得到肯定结果,如怀疑试剂已变质应进行___。
A. 重复实验
B. 对照实验
C. 空白试验
D. 灵敏性试验
【单选题】
[1]在同样的条件下,用标样代替试样进行的平行测定叫作___。
A. 空白实验
B. 对照实验
C. 回收实验
D. 校正实验
【单选题】
[2]带有玻璃活塞的滴定管常用来装___。
A. 见光易分解的溶液
B. 酸性溶液
C. 碱性溶液
D. 任何溶液
【单选题】
[3]天平零点相差较小时,可调节___。
A. 指针
B. 拔杆
C. 感量螺钉
D. 吊耳
【单选题】
[3]使用电光分析天平时,取放物体时要托起横梁是为了___。
A. 减少称量时间
B. 保护玛瑙刀口
C. 保护横梁
D. 便于取放物体
【单选题】
[2]BpH=5.26中的有效数字是___位。
【单选题】
[2]下列有关置信区间的定义中,正确的是___。
A. 以真值为中心的某一区间包括测定结果的平均值的概率
B. 在一定置信度时,以测量值的平均值为中心的,包括真值在内的可靠范围
C. 总体平均值与测定结果的平均值相等的概率
D. 在一定置信度时,以真值为中心的可靠范围
【单选题】
[3]要准确量取25.00mL的稀盐酸,可用的量器是___。
A. 25ml的量筒
B. 25ml的酸式滴定管
C. 25mL的碱式滴定管
D. 25mL的烧杯
推荐试题
【单选题】
- Sorry to have kept you waiting. ____
A. That's OK.
B. What are you doing?
C. What's wrong with you?
D. Where have you been?
【单选题】
- What is she?____
A. She is a typist.
B. She is talking to her friend.
C. She is having a holiday.
D. She is my sister.
【单选题】
- That's a beautiful cat. I wonder who it belongs to.____
A. It belongs to the
B. rowns. B.The cat is my favourite too.
C. Mind your own business.
D. I can't say anything more.
【单选题】
- Excuse me, could you tell me the time____
A. You'd better buy a watch.
B. It's three thirty by my watch.
C. Can you see the clock?
D. It's late I think.
【单选题】
- What do you think of the movie we saw last night?____
A. The actress is bad.
B. Terrific!
C. The theatre is bad.
D. Nobody was there.
【单选题】
___ No, thanks. I'm just looking around. I'll let you know if I want anything.
A. Could you help me?
B. What will you buy?
C. Can I help you?
D. Do you like to look around?
【单选题】
- Hello, Peter. What do you do?____
A. I am fine.
B. I am not sick.
C. I am a student from Bonn University.
D. I came from Bonn University.
【单选题】
-Excuse me; can I have a seat here?___
A. Be hurry.
B. Come on.
C. Yes, please.
D. Do you mind?
【单选题】
- Shall we sit up here on the grass or down there near the water?___
A. I'd rather stay here if you don't mind.
B. Sorry, I don't like neither.
C. Certainly, why not?
D. Yes, we like these two places.
【单选题】
- What do you do on Sunday?___
A. I 'm a teacher.
B. I play football.
C. You are a student.
D. They clean rooms.
【单选题】
- Our class won the girls' relay race in our school's sports meeting.___
A. That's right.
B. Thanks a lot.
C. Congratulations!
D. It's a pleasure.
【单选题】
- Hi, is Mary there, please?___
A. Hold on. I'll get her.
B. No, she isn't here.
C. Yes, she lives here.
D. Yes, what do you want?
【单选题】
- I am afraid I can't return the book to you before Friday. ___
A. Don't be afraid
B. Be careful
C. Not at all
D. Take your time
【单选题】
- I really don't know how to thank you enough. ___.
A. No problem
B. Think nothing of it
C. Not at all
D. It doesn't matter
【单选题】
- Must I be home before seven? ___.
A. No, you needn't
B. No, you mustn't
C. Yes, you will
D. No, you won't
【单选题】
-I'm sorry to hear that you failed in the exam______.
A. Not at all
B. Oh, thank you.That's very kind of you
C. You are welcome
D. Yes, I'm really sorry
【单选题】
-I will,______.
A. that's all right
B. thank you
C. all right
D. not at all
【单选题】
-Hello, may I speak to Zhao Hua?_____.
A. My name is Zhao Hua
B. I'm Zhao Hua
C. This is Zhao Hua speaking
D. Zhao Hua is me
【单选题】
___This is Mr Smith speaking now.
A. Who are you
B. Who is that
C. Who are you calling
D. What do you want to say
【单选题】
- I was worried about my maths, but Mr. Brown gave me an A.___
A. Don't worry about it.
B. Congratulations! That's a difficult course.
C. Mr. Brown is very good.
D. Good luck to you!
【单选题】
-Would you go to the concert with me?___, but I'm very busy now.
A. I'd like to
B. Sure
C. No problem
D. Certainly
【单选题】
-I'll be away on a business trip. Would you mind looking at my cat?Not at all. _______.
A. I have no time
B. I'd rather not
C. You can leave
D. I'd be happy to
【单选题】
- Hi, Jim! Nice to meet you.____.
A. Certainly
B. Many thanks
C. OK
D. Nice to meet you, too
【单选题】
- Hello, may I speak to Mike?_____
A. Who are you?
B. Sorry, he isn't in.
C. Thank you very much.
D. Yes, here you are.
【单选题】
- Will you join us for lunch?____.
A. No, I won't
B. Yes, with pleasure
C. Yes, please
D. Yes, help yourself
【单选题】
- Thank you for your great dinner. I really enjoyed it._____you enjoyed it.
A. I'm so glad
B. I'm sorry
C. What a pity
D. Surprisingly
【单选题】
- I heard Susan surprised her teacher by working hard. Yes, ___
A. her teacher worked hard.
B. Susan worked hard.
C. the teacher was surprising.
D. Susan was surprised.
【单选题】
- Peter, don't step on the grass_______.
A. It doesn't matter
B. I can't do it
C. Don't worry
D. Sorry, I won't do it again
【单选题】
- How was your journey to Paris? - ____
A. It went very well.
B. I flew there.
C. I love Paris.
D. Thank you for asking.
【单选题】
- I'm sorry for being late, Mr Lt______.
A. All right
B. That's right
C. Not at all
D. Never mind
【单选题】
- Happy birthday to you! ___!
A. Happy birthday to you
B. I'm very glad
C. That's all right
D. Thank you
【单选题】
- Do you like country music?___.
A. Yes, I like basketball a lot
B. It's far too crowded
C. Yes, I'm crazy about it
D. Oh, it's funny
【单选题】
- Have a cup of tea, ____? Thanks a lot.
A. don't you
B. haven't you
C. shall we
D. will you
【单选题】
- Thank God.It's Friday again.A nice weekend!___.
A. Me too
B. Yes,I'll be free then
C. That's all right
D. The same to you
【单选题】
— Write to me when you get home. OK, I ______.
A. must
B. should
C. will
D. can
【单选题】
Tom is so talkative. I’m sure you'll soon get tired ___ him.
A. of
B. with
C. at
D. on
【单选题】
I don't know ____ to deal with such matter.
A. what
B. how
C. which
D. /
【单选题】
___ is your girl friend like? She is very kind and good-looking.
A. How
B. What
C. Which
D. Who
【单选题】
He ___ driving me home, even though I told him I lived nearby.
A. insisted on
B. insisted at
C. insisted that
D. insisted in
【单选题】
We came finally ___the conclusion that she has been telling lies all the time.
A. of
B. into
C. to
D. at