二氧化硫是重要的工业原料,探究其制备方法和性质具有非常重要的意义. (1)工业上

题型:问答题

问题:

二氧化硫是重要的工业原料,探究其制备方法和性质具有非常重要的意义.

(1)工业上用黄铁矿(FeS2,其中S元素为-l价)在高温下和氧气反应制备SO2:4FeS2+11O2

 高温 
.
 
8SO2+2Fe2O3,该反应中被氧化的元素是______(填元素符号).当该反应转移2.75mol电子时,生成的二氧化硫在标准状况下的体积为______L.

(2)实验室中用如图1所示的装置测定SO2催化氧化为SO3,的转化率.(已知SO3熔点为16.8℃,假设气体进入装置时分别被完全吸收,且忽略空气中CO2的影响.)

①简述使用分液漏斗向圆底烧瓶中滴加浓硫酸的操作是______.

②实验过程中,需要通入氧气.试写出一个用图2所示装置制取氧气的化学方程式______.

③当停止通入SO2,熄灭酒精灯后,需要继续通一段时间的氧气,其目的是______.

④实验结束后,若装置D增加的质量为m g,装置E中产生白色沉淀的质量为n g,则此条件下二氧化硫的转化率是______(用含字母的代数式表示,不用化简).

(3)某学习小组设计用如图3装置验证二氧化硫的化学性质.

①能说明二氧化硫具有氧化性的实验现象为______.

②为验证二氧化硫的还原性,充分反应后,取试管b中的溶液分成三份,分别进行如下实验:

方案I:向第一份溶液中加入AgNO3溶液,有白色沉淀生成

方案Ⅱ:向第二份溶液加入品红溶液,红色褪去

方案Ⅲ:向第三份溶液加入BaCl2溶液,产生白色沉淀

上述方案中合理的是______(填“I”、“Ⅱ”或“Ⅲ”);试管b中发生反应的离子方程式为______.

③当通入二氧化硫至试管c中溶液显中性时,该溶液中c(Na+)=______(用含硫微粒浓度的代数式表示).

考点:二氧化硫
题型:问答题

主要用来隔断电源,以保证检修和倒闸操作的安全没有专门的灭弧装置,不能用来接通和分类负荷电流,更不能用来切断短路电流的高压开关是( )。

A.高压断路器

B.高压负荷开关

C.隔离开关

D.熔断器

题型:问答题

Why does the rate of heart attacks increase during the World Cup football finals? How can we help an overweight patient to lose weight? They’re just some of the topics covered in a new book by University of Sussex academics, which is helping student doctors to consider the importance of psychology in medical practice.

Psychology for Medicine is the first textbook of its kind, providing medical trainees and new doctors with all the relevant psychological knowledge they need. Previously, students had to refer to many different books for the relevant psychology.

The book, by Sussex psychologists Dr. Sussex Ayers and Dr. Richard de Visser, has been well received by fellow academics and medical doctors and was finished with the help of the students and staff of the Brighton and Sussex Medical School. The students proofread(校对) the chapters, provided ideas for the content and even modeled for the photographs. The book provides a solid grounding in psychological study relevant to medicine, along with practical tips and advice for practice. One student, Simon Hall, drew cartoons for the book.

The study psychology is important for doctors for a number of reasons. Psychological and physical symptoms are highly related. Up to a third of patients will have psychological disorders, while physical causes are usually only found in around 15 per cent of people’s symptoms. In treatment, a lot of the effect drugs can be due to patients believing they will recover rather than the drug itself.

Dr. Ayers says, “The important thing about this book is that it’s applied science --- it shows why psychology is important to medicine and how we should use it. The book’s presentation is really important. It’s not just lots of theory, but full of tips and advice so that students can take what they learn in the classroom and apply it to real-life situations.”

小题1:The book Psychology for Medicine is mainly written for ________.

A.scientists

B.overweight people

C.patients

D.student doctors小题2:What is the third paragraph mainly about?

A.The topics of the book.

B.The comments on the book.

C.The contributors to the book.

D.The characteristics of the book.小题3:According to the text, the book Psychology for Medicine _________.

A.is a bit difficult to understand.

B.is mainly about how to lose weight.

C.included tips on training football players.

D.focuses on the importance of psychology in treatment小题4:We can infer that the text is a(n) ______.

A.research report

B.introduction to a book

C.advertisement for a book

D.introduction to a psychologist

题型:问答题

Brodie根据头部X线片观测,提出了颅面部生长发育的特点。以下哪项描述不属于Brodie所提到的特点,或者是错误的描述()

A.面部的生长型在儿童的早期就已确定

B.头颅增长的速度,随年龄的增加而递减

C.在增长过程中,头部的多点按直线方向推进

D.鼻腔底、牙弓面、下颌体下缘三者与Bolton平面之间的交角,随年龄增加而逐渐增大

E.由蝶鞍中心通过上颌第一恒磨牙到颊部所画的直线,可以代表面部向前向下增长的综合方向

题型:问答题

企业办理异地开证、付汇时,须凭下列()单证到企业所在地外汇局办理类别为“异地付汇”的进口付汇备案手续。

A、加盖企业公章的备案申请函

B、进口合同

C、代理协议(委托代理项下)

D、外汇局规定的单据

题型:问答题

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