问题 实验题

某化学小组在实验中利用CaSO4、NH3、CO2制备(NH4)2SO4,其工艺流程如下。

回答下列问题:

(1)操作Ⅰ的名称为_________;操作Ⅱ一系列操作包括蒸发浓缩、________、过滤。

(2)实验室中煅烧碳酸钙时,盛放碳酸钙所用的仪器是________(填名称)。

(3)X物质为____(填化学式,下同),Y物质为____,可循环利用的物质的有_____。

(4)要测定所制得的硫酸铵纯度,取10.0g样品,完全溶于水,向溶液中滴加过量的氯化钡溶液,过滤、洗涤、干燥后称量固体的质量为16.31g。为避免引起误差,检验氯化钡溶液是否过量最好的试剂是_______,所制得硫酸铵的纯度为________。

(5)下列装置不能用于实验室制氨气的是__________(填序号)。

选择氨气的制取装置后,再用下列装置收集干燥的氨气,并制取硫酸铵溶液,连接的顺序(用接口序号字母表示)是:a接____,____接____,____接_____,____接_____。

上述装置中CCl4的作用是___________________。

答案

(1)过滤(1分),冷却结晶(2分,少一方面扣1分)

(2)坩埚(1分)

(3)NH3、CO2; NH3,CO2(每种物质均为1分,最后一空少一种扣1分,错一种倒扣1分)

(4)氯化钡溶液(2分,),92.4%(3分)

(5)甲(2分),de,gf,cb,h(2分);防倒吸(1分)

题目分析:(1)经过操作I得到CaCO3固体和滤液,所以操作I为过滤;硫酸铵的溶解度随温度的降低而减小,所以蒸发浓缩后进行冷却结晶。

(2)实验室中高温煅烧固体的容器为坩埚。

(3)根据题目信息:某化学小组在实验中利用CaSO4、NH3、CO2制备(NH4)2SO4,由于CO2在水中溶解度较小,而NH3易溶于水,应先通入足量NH3,使溶液呈碱性,然后再通入适量CO2,所以X为NH3、Y为CO2;根据反应流程图可以看出在后续反应中又生成了CO2和NH3,所以可循环利用的物质的有CO和NH3

(4)最好的试剂是氯化钡溶液,因为再加入氯化钡溶液后,不会对BaSO4的量产生误差;硫酸铵与硫酸钡的对应关系为:(NH4)2SO4 ~ BaSO4所以硫酸铵的纯度=16.31g×132/233÷10.0g×100%=92.4%

(5)甲、直接加热NH4Cl生成 NH3和HCl,在试管口附近NH3和HCl反应又生成了NH4Cl,所以不能用来制取NH3,错误;乙、加热浓氨水促进NH3的挥发,可制取NH3,正确;丙、加热氢氧化钙和氯化铵固体,发生复分解反应生成NH3,可用于制取NH3,正确;丁、浓氨水滴加到NaOH固体中,可挥发出NH3,能用于制取NH3,正确;因为要收集干燥的NH3,所以a后接de,碱石灰干燥NH3,后面连接gf,收集NH3,后面连接cb,通入稀硫酸,制取硫酸铵,后面连接h,进行尾气处理;把NH3直接通入稀硫酸中会发生倒吸,而NH3难溶于CCl4,所以CCl4的作用是防倒吸。

阅读理解

Millions of British people have ditched the traditional “thank you” and replaced it with the less formal “cheers”, according to a survey.

Although the average person will say “thank you” nearly 5,000 times a year, one in three are more likely to throw in a “cheers” or “ta” where it’s needed, rather than risk sounding old fashioned.

One in 20 now say “nice one” instead, while younger generations are more likely to offer a “cool” than a “thank you”. “Merci”, “fab” and even “gracias” were also listed as common phrases to use, as was “much appreciated”.

One in twenty who took part in the survey of 2,000 people by the Food Network UK for Thank You Day, which is marked on November 24, 2011, said a formal “thank you” was now not often needed in everyday conversation. More than one in ten adults said they regularly wouldn’t say “thank you” if they were in a bad mood.

Most people declared that saying “thank you” was something drilled into them by their parents. A huge 70 percent of those questioned will say “thank you” to a person’s face without even meaning it, while a fifth avoid saying it when they know they should — on at least two occasions every day.

It seems our friends and family get the brunt (压力) of our bad manners with half admitting they’re not good at thanking those closest to them — many justifying (为……辩解) the lack of thanks because their family “already know I’m grateful”.

When spoken words won’t do, it falls to a nice text to do the job for most people. A thank you email is also popular, while a quarter turn to social networks to express gratitude. A quarter of British people say thank you with food, with 23 percent cooking a meal to show their appreciation to someone. Another 15 percent bake a cake. A third will still send a handwritten thank-you note — but 45 percent admit it’s been more than six months since they bothered to send one.

It follows that 85 percent of people will be annoyed at not getting the gratitude they feel they should receive. 

小题1:Most of the people who took part in the survey say that they say “thank you” _____.

A.when they are in good mood

B.completely out of habit

C.when they feel truly grateful

D.purely out of politeness小题2:The underlined word “ditched” in Paragraph 1 means “_____”.

A.abandoned

B.used

C.shared

D.grasped小题3:It can be learned from the passage that _____.

A.different ways of expressing gratitude are all fashionable

B.people should avoid saying “thank you” nowadays

C.a thank-you note is still appreciated by most people

D.people in a bad mood never say “thank you”小题4:Which of the following is TRUE according to the passage?

A.Most people express their gratitude to others by buying food for them.

B.About fifty percent of people try not to say thank you when they should.

C.Most people may feel natural when they fail to receive others’ gratitude.

D.Many people think it unnecessary to say thanks to their family members.

单项选择题