相关试题
【判断题】
金属离子指示剂与金属离子生成的络合物过于稳定称为指示剂的僵化现象
【判断题】
测定H2C2O4·2H2O的莫尔质量时,所用的试样失去部分结晶水，产生正误差
【填空题】
1.如果基准物未烘干，将使标准溶液浓度的标定结果___。
【填空题】
2.移液管移取溶液时，当液面上升至标线以上，应用___堵住管口。
【填空题】
3.标定EDTA溶液时，若控制pH=5，常选用___为金属离子指示剂；若控制pH=10，常选用EBT为金属离子指示剂。
【填空题】
4.在滴定操作中___手控制滴定管，___手握锥形瓶；滴定接近终点时，应控制半滴加入，加入半滴溶液的方法是___。滴定完毕进行读数时，应___。
【填空题】
5.测定水的总硬度时用___掩蔽Fe3+、Al3+等少量共存离子。
【填空题】
6.NaOH标准溶液因保存不当吸收了CO2，若以此NaOH溶液滴定H3PO4至第二个计量点,则H3PO4的分析结果将___。
【填空题】
7.浓HCl的大致浓度为___mol/L、浓H2SO4的大致浓度为___mol/L、浓HNO3的大致浓度为___mol/L、浓NH3水的大致浓度大致为___mol/L。
【填空题】
8.移液管吸取溶液时___手拿移液管，___手拿吸耳球。
【填空题】
9.用EDTA直接滴定有色金属离子，终点所呈的颜色是___。
【填空题】
10.A[纵坐标]～λ[横坐标]作图为___曲线，A[纵坐标]～C[横坐标]作图为___。
【填空题】
11.标定氢氧化钠的基准物质有___和___.
【填空题】
12.使用水蒸气蒸馏装置蒸馏产物，可使产物在低于___℃的情况下被蒸出。
【填空题】
13.分馏操作的加热强度应该稳定、均衡并采取适当的保温措施,以保证柱内形成稳定的___梯度、___梯度和___梯度。
【填空题】
14.测定熔点用的毛细管直径约为___，样品在其中装载的高度约为___。
【填空题】
15.油泵减压蒸馏的装置比较复杂，大体上可分为三大部分，即___部分、___部分、___部分。
【填空题】
16.液体有机化合物的干燥方法有___干燥法和___干燥法两种，干燥剂用量一般约为产物重量的___，视___的多少而定，至少干燥___h，蒸馏前必须___。
【填空题】
17.控制加热速度是熔点测定准确与否的关键操作。开始时加热速度可___，待升温至熔点以下10~15℃时，应调节火焰使每分钟上升___。
【填空题】
18.薄层层析点样时，用内径小于___的平口毛细管点样，其样点的直径应不超过___，若在同一快板上点两个以上样点，样点间应相距___。
【填空题】
19.在重结晶时往往需要加入脱色剂煮沸以除去其中的___杂质和___杂质。脱色作用的原理是___，脱色剂的用量一般为粗样品重量的___。10.在制备三苯甲醇的实验中，格氏反应所用溶剂通常为___。这一方面是因为___，可借___排开大部分空气，减少___的接触；另一方面是___可与格氏试剂配位络合，溶于___。
【填空题】
20.重结晶的滤集晶体步骤中常需用新鲜溶剂洗去晶粒表面粘附的母液。正确的洗涤方法是先___，再加入少量新鲜溶剂，小心地用刮匙将晶体___，使溶剂浸润全部晶体，然后___。
【填空题】
21.芳香醛与羧酸酐在弱碱催化下生成___的反应称为___反应。
【判断题】
测定水的硬度时,需要对Ca、Mg进行分别定量
【判断题】
对某项测定来说，它的系统误差大小是不可测量的
【判断题】
金属离子指示剂与金属离子生成的络合物过于稳定称为指示剂的封闭现象
【判断题】
以HCl标准溶液滴定碱液中的总碱量时，滴定管的内壁挂液珠，会使分析结果偏低
【判断题】
NaHCO3中含有氢，故其水溶液呈酸性
【判断题】
金属离子指示剂与金属离子生成的络合物过于稳定称为指示剂的僵化现象
【判断题】
测定H2C2O4·2H2O的莫尔质量时,所用的试样失去部分结晶水，产生正误差
【填空题】
1.如果基准物未烘干，将使标准溶液浓度的标定结___。
【填空题】
2.移液管移取溶液时，当液面上升至标线以上，应用___手___指堵住管口。
【填空题】
4.标定EDTA溶液时，若控制pH=5，常选用___为金属离子指示剂；若控制pH=10，常选用___为金属离子指示剂。
【填空题】
5.在滴定操作中___手控制滴定管，___手握锥形瓶；滴定接近终点时，应控制半滴加入，加入半滴溶液的方法是___；滴定完毕进行读数时，应将滴定管___视线应与___。
【填空题】
6．测定水的总硬度时用___掩蔽Fe3+、Al3+等少量共存离子。
【填空题】
7．NaOH标准溶液因保存不当吸收了CO2，若以此NaOH溶液滴定H3PO4至第二个计量点,则H3PO4的分析结果将___。
【填空题】
1、浓HCl的大致浓度为___mol/L、浓H2SO4的大致浓度为___mol/L、浓HNO3的大致浓度为___mol/L、浓NH3水的大致浓度大致为___mol/L。
【填空题】
3、移液管吸取溶液时___手拿移液管，___手拿吸耳球。
推荐试题
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
The new government has committed to [ ] emissions of greenhouse gases
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
My parents do not object to my taking part-time jobs, but they remind me not to let them [ ] my school work
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Anger, worry, disappointment, these negative emotions [ ] your heart, brain and body
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
If a person adopts an unhealthy lifestyle, he will surely be [ ]developing diseases.
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Most people were ready to give up on him when he [ ] of school, but later he returned and earned his degree
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Drinking too much can increase the risk of developing high blood pressure, which [ ] can lead to heart attack or stroke
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Low-cost airlines are emerging all over Asia; this will [ ]the development of the worlds air-travel market as a whole
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
When you move to a new country, you may find the food there strange and you may miss the familiar smells of the food [ ] in your country
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Although he kept trying and failing, I always [ ] the belief that he would succeed one day.
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
The tax only affects people with an annual income over $200,000-[ ], it will only attect the very rich.
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Studies[ ]that children who often take part in cooperative programs benefit a lot more than other children
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
They are such a(n) [ ] family- they must have been shocked when their son dyed(染) his hair pink,
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Testing students by examinations has long been regarded as a reliable way to [ ]students'ability
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Many power stations have been modernized to give off less pollution, or they were moved further away from the living areas in order to [ ] the damage,
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Unemployment has come down slightly, but this does not [ ]the fact that it is still a major problem
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Mr. Smith is not doing well; the doctor told us that several colds [ ]his health
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
The best way to deal with problems at home is to talk things out calmly and honestly and try to reach a(n) [ ]
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Experts say our company is amazing in that sales have been increasing steadily [ ]
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
After 10 years of full-time training, she has,finally [ ] as a professional dancer.
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
[ ], what is the point in taking part in the competitive event if the result is only to prove how incompetent you are?,
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Redecorating the house is a challenging task. It's necessary to [ ] the wallpaper first.
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
I never really had any problems with change. On the contrary, I welcome change [ ]
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
A lot of what we [ ] is made from raw materials which are not renewable
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Megan and John realized that their house was too messy for a new baby, so they decided to [ ] their house before the baby was born
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Jennifer couldn't [ ] her tears when she saw the sick children at a new blood cancer center in Virginia
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
We want to give all children a world [ ] violence
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
Fortunately, the accident didn't [ ] many people, for there was little traffic at that hour.
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
She[ ] her ambition of becoming a fashion designer after years of hard work
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
They kept on trying their best to develop
their business, but in such [ ]market competition, they had no Idea if success would come along one day
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
As music plays an important role in our life, many music teachers and educators [ ] taking up a musical instrument at a young age
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
This rule should be entirely clear in the minds of everyone and should not be misunderstood under any [ ]
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
My daughter was shy; she was afraid to ask questions,[ ] to questions in class,or talk with other children
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
I got from him only a letter, which was put on my office desk; [ ] to the receipt of this letter I have never heard from him
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
The duties to provide services for children in need are not [ ] to the local social services department
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
We pray that all nations be [ ] and that all people around the world live in peace
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
It was reported the president had [ ]to fight If war was necessary,even if it meant destroying his chances of re-election
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
I had to [ ] one of my email accounts as it was filled with junk mail
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Darwin's theory of evolution remains[ ] partly because it challenges the religious belief that God created man
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
He suggested a small but [ ] improvement on our former plan; I really appreciate it.
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
She held her hand above her eyes to [ ]them [ ] the sun so that she could see more clearly the man in front of her
