(14分)碳酸锶广泛应用于电子工业。以天青石(主要成分为SrSO4)为基本原料制

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问题:

(14分)碳酸锶广泛应用于电子工业。以天青石(主要成分为SrSO4)为基本原料制备碳酸锶。

(1)碳还原法制备。

①已知:SrSO4(s) + 4C(s) 4CO(g) + SrS(s)   △H=+a kJ·mol-1     

SrSO4(s) + 2C(s)2CO2(g) + SrS(s)   △H=+b kJ·mol-1     

则:反应C(s) + CO2(g)2CO(g)的△H= ___________kJ·mol-1

②SrS是强碱弱酸盐,热水中发生水解的化学反应方程式为_______________________。

③水解所得Sr(OH) 2与NH4HCO3按照物质的量比1:1投料制备SrCO3,则化学反应方程式为__________________________________________________。

(2)湿法制备。(已知:Ksp(SrSO4)=3.2×10-7Ksp(SrCO3)=1.1×10-10。)

①将天青石矿粉与Na2CO3溶液搅拌混匀、加热,发生的离子反应方程式为: ____________。

②当转化完成时,混合液中c(CO32-)= 1.0×10-3mol/L,c(SO42-)=______________mol/L。 

考点:光导纤维新型材料(新型陶瓷、单晶硅等)塑料、纤维、橡胶复合材料
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接触铬酸盐工人易患的职业肿瘤是()

A.皮肤癌

B.肺癌

C.肝血管肉瘤

D.白血病

E.间皮瘤

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(11分)下列是“检测教室中的细菌和真菌”的实验步骤:

①用牛肉汁(或土壤浸出液、牛奶)与琼脂混合配制培养基;

②将配制好的培养基平铺在两个培养皿中进行高温处理,冷却后使用;

③在教室打开培养皿A ,暴露在空气中10分钟,再盖上,封好。培养皿B不做任何处理。④将两套培养皿同时放入恒温箱中培养,几天后观察培养皿中菌落的生长情况。

(1)在第2步操作中培养皿和培养基进行了高温处理,目的是                     

(2)步骤3的操作,相当于细菌、真菌一般培养方法中的哪一个步骤?

                            

(3)在实验过程中选取两套培养皿的目的是                        

(4)如果实验成功,几天后观察培养皿中的菌落,会发现培养皿     中的没有菌落生长。

(5)真菌的结构包括                                  四部分,根据组成身体的细胞数量的多少可以分为                          两类。真菌与细菌的区别在于细菌没有                   

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起自髂骨、骶骨、尾骨及骶结节韧带的背面,止于股骨的臀肌粗隆和髂胫束的肌是()

A.臀大肌

B.梨状肌

C.闭孔内肌

D.闭孔外肌

E.臀中肌和臀小肌

题型:填空题

对泌尿系统有毒性的药物是()

A.马钱子

B.蟾酥

C.关木通

D.枳实

E.苦杏仁

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What makes Reader’s Digest the most successful magazine in publishing history Beneath the fun and excitement that fill our pages, we are, above all else, a serious magazine. Our readers are serious people. The Digest never loses sight of the fact that each day all of us confront a tough, challenging world. To millions who know our record of viewing this world, we are not a luxury; we are a necessity.

Basic to our magazine is a steady focus on the power of the individual. We show that man’s greatest ideas and accomplishment, his often stunning (极好的) faith and courage and hope, can be seen in the conduct of ordinary men and women. We reflect the universal skepticism that government can solve our problems; we herald the unending promise of self-determination and individual enterprise. Readers depend upon us for truth and accuracy, logic and common sense.

Our stories come from the grit of human experience-the tough, the tender, the funny. These stories—always told in a powerful narrative style—spring from love and caring, from a sense of right and wrong, from a dedication to the vitality (活力,生命力) of the human spirit. We are at the forefront of major issues of medicine, health, environment, human rights. We take readers behind the headlines to the cause and meaning of world events. We celebrate courage, champion adventure and always seek to expand the mind, and to enrich the spirit and the body. It is this clear voice—never preaching (说谎), always showing-that has made readers set us apart from all other magazines.

Deep within our widely varied package of humor, drama, and helpful information, there hums (哼唱) a subtle power that guides people in every aspect of their lives. They listen because what we put forth rings true. They are comfortable with our clear, concise words that inform them, entertain them, and remind them of those eternal values that fortify all decent people as they seek clarity and coherence in a confusing world. Our readers recognize that our compass is good for the long haul-that our principles are good for all seasons, good for all ages, good for all those who wish to play a role in making their world a better place. So long as we never lose sight of these powerful principles that are at the soul of our magazine-and so long as we remain at the cutting edge of life in our world—then we are prepared to lay claim to a future as brilliant and as exciting as our past.

According to the passage, the Digest will have a bright future as long as ()。

A. it holds the principles as it has been doing in the past

B. it keeps pace with the latest development of the world’s situation

C. it keeps its language clear, concise and easy to understand

D. it combines serious themes of life with a sense of humor

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