(1)用油膜法估测分子的大小时有如下步骤: A、将玻璃板放在浅盘上,然后将油酸膜

题型:填空题

问题:

(1)用油膜法估测分子的大小时有如下步骤:

A、将玻璃板放在浅盘上,然后将油酸膜的形态用彩笔画在玻璃板上;

B、将油酸和酒精按一定比例配制好;

C、向浅盘中倒入约2cm深的水;

D、把酒精油酸溶液一滴一滴滴入量筒中,当体积达到1ml时记下滴入的滴数,算出每滴液滴的体积;

E、向浅盘中的水面均匀地撒入石膏粉(或痱子粉);

F、把一滴酒精油酸溶液滴在水面上,直至薄膜形态稳定;

G、把玻璃板放在方格纸上,数出薄膜所占面积;

H、计算出油膜的厚度L=

V
S

把以上各步骤按合理顺序排列如下:______

(2)若油酸酒精溶液的浓度为每104ml溶液中有纯油酸6mL,用注射器测得1mL上述溶液有液滴75滴.把1滴该溶液滴入盛水的浅盘里,最后油酸膜的形状和尺寸如图所示,坐标中正方形小方格的边长为1cm,则

①油酸膜的面积是______m2

②每一滴油酸酒精溶液中含有纯油酸的体积是______m3

③按以上数据,估测出油酸分子的直径是______m.

考点:实验:用油膜法估测分子的大小
题型:填空题

Perfume (香水) has been in existence for a long time. These days, certain perfumes are considered comparable to great works of art. Here are a few of the most famous perfumes in history.

Chanel No.5

This perfume is probably the best-selling scent (气味) in the history of fragrance (香水). Created by Ernst Beaux for Coco Chanel in 1921, it has been described as “the world’s most legendary fragrance”, and remains the company’s most famous perfume.

Shalimar

Jacques Guerlain created this vanilla (香草) fragrance in 1925. The perfume takes its name from the Garden of Shalimar, which was built by Emperor Shah Jehan for one of his wives. It was an immediate hit in 1925 and is still extremely popular today.

Joy

Joy is famous for having been the most expensive perfume in the world at one point. It was created in 1930 by Henri Alméras for Jean Patou to lift the bad mood that had swept over the world after the 1929 stock market crash.

L’Air duTemps

Francis Farbon created Nina Ricci’s L’Air du Temps in 1948. The fragrance is known for its spicy (香的) carnation (康乃馨) and gardenia (栀子) scents as well as its beautiful crystal (水晶的) bottle (designed by Lalique).

Eternity

Calvin Klein’s second perfume was created by Sophia Grojsman in 1988. Known for its light, flowery scent, the perfume was listed in the Fragrance Hall of Fame in 2003. It is recommended for daytime wear.

Angel

This wildly popular perfume was created in 1992 by Olivier Cresp for Thierry Mugler. The perfume was an instant success. The perfume has often been described as “delicious”, owing to its chocolatey (巧克力味的) scent. The perfume comes in beautiful star-shaped bottles. Angel perfume also comes in several bath and body products.

小题1:Who created Joy?

A.Henri Alméras.

B.Jean Patou.

C.Sophia Grojsman.

D.Jacques Guerlain.小题2:Which of the following perfumes is known for its wonderful crystal bottle?

A.Shalimar.

B.Chanel No. 5

C.L’Air du Temps.

D.Eternity.小题3:The Angel perfume has been described as delicious because of __________.

A.its spicy scent

B.its special bottle design

C.its vanilla scent

D.its chocolatey scent小题4:Which of the following statements is TRUE?

A.Emperor Shah Jehan created the Shalimar perfume for one of his wives.

B.Joy was created to cheer people up after the stock market crash.

C.Lalique created Nina Ricci’s L’Air du Temps in 1948.

D.Eternity was listed into the Fragrance Hall of Fame in 1988.小题5:Where can you probably see this article?

A.In a textbook.

B.In the newspaper.

C.In a travel magazine.

D.In a fashion magazine.

题型:填空题

临床器官移植常用的免疫抑制剂有()

A.皮质类固醇

B.FK506

C.环磷酰胺

D.抗淋巴细胞球蛋白

E.环孢素

题型:填空题

( )决定一国生活水平提高的速度。

A.经济增长

B.经济扩张

C.利润盈余

D.财务稳健

题型:填空题

甲公司向乙建材商订购了一批木料。乙按照约定将木料置于交付地点并告知了甲公司,但甲未按约定时间收取。这期间,木料堆放地失火,导致甲订购的部分木料被毁。此损失应由()。

A.甲和乙各分担一半

B.乙全部承担

C.甲承担大部分责任

D.甲承担全部责任

题型:填空题

某同学设计了图所示装置(夹持仪器省略)进行系列实验,实验时将药品A逐滴加入到固体B中,请回答:

(1)若A为浓氨水,B为烧碱,C为AlCl3溶液,打开分液漏斗旋塞,烧瓶中即有氨气生成,

原因是______(结合离子方程式回答).一段时间后,观察到试管中的现象是______,

发生反应的离子方程是______.

(2)利用该装置设计实验证明醋酸、碳酸、苯酚的酸性强弱,若B为碳酸钠,A与B发生反应的离子方程式是______,能得到的相应结论是______;试管中出现浑浊,依据此现象能否得出相应的结论,请简述理由:______.

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