氢、碱金属和碱土金属课件.ppt

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1、氢、碱金属和碱土金属 Hydrogen , Alkali and Alkali-earth metals,1氢及其化合物（Hydrogen ant its compounds）,氢在周期表中排A，又能排A，这是由于第一周期的稀有气体电了构型为1s2 。 一、单质氢（Simple substance of hydrogen） 1、氢的同位素（isotope） (1) P P+n P+2n Protium Deuterium Tritium 氕 氘 氚,(2)存在：H:D=6800:1(原子个数) H:T=1e10:1,Heat,Cool,(4) 氢同位素形成的单质H2、D2、T2,在化学性质上完

2、全相同，但物理性质（熔沸点）上有差别。2. Properties: (1) Physical properties: H2：极难溶于水和有机溶剂，可以贮存在金属(Pt、Pd)和合金(LaNi5)中 固态氢（黑色）又称为金属氢：在晶格质点上为质子，而电子为整个晶体享，所以这样的晶体具有导电性，固态氢可能为立方或六方分子晶格。,(2)Chemical properties: a. 成键特点：电子构型为 1s ，可以放在A类， 但第一电离势高于碱金属的第一电离势；也可放在 A类。 b. 化合反应：与金属: 2Na + H2 = 2NaH Ca + H2 = CaH2 与非金属: H2 + F2 =

3、2HF c. 还原反应： CuO + H2 = Cu + H2O WO3 + 3H2 = W + 3H2O,3.Preparation (1) 实验室： (2)工业上：,二、氢化物（Hydride）放在以后各章元素中讲解,http:/www.chemsys.t.u-tokyo.ac.jp/laboratory_domen-kubota_e.html,Si(s) +Ca(OH)2(s) +2 NaOH (s) = Na2SiO3(s) +CaO (?)+ 2H2(g),2碱金属元素及其化合物 Alkali metals and their compounds Lithium Sodium Pot

4、assium Li Na K Rubidium Cesium Francium Rb Cs Fr,for structural and mechanistic studies of ion channels,Roderick MacKinnon,The Nobel Prize in Chemistry 2003Peter Agre, Roderick MacKinnon,K+ channel,I was born on February 19, 1956 in the middle of a snowstorm. It remains one of those humorous family

5、stories that my mother likes to tell. My father the planner had rehearsed the way to the hospital but apparently things looked a lot different at night in a blizzard. Eventually they made it and so did I, the fourth of seven children. My father was a postal worker when I was very young but studied c

6、omputers and became a programmer on the big IBM main frames. My mother worked as a part time schoolteacher, but mostly took care of the children at home. Thinking back on it now I know we did not have much money but I never knew that growing up. My parents provided a happy environment and made their

7、 expectations clear to us. Television is bad for you, reading is good for you, and you better get an A for effort in school. What you end up doing in life is up to you. Just make sure you enjoy what you do because then you will do it well. We all pursued completely different walks of life. I became

8、the scientist.I suppose there were some early indications of my tendency to a life of curiosity. Apparently from a very young age I had a habit of asking lots of questions: what would happen if.? was a favorite. And I liked having facts straight and knowing how things work and did not hesitate to gi

9、ve explanations to those around me, apparently to an annoying degree sometimes. I remember one day my father, at the end of his patience, commenting that I was a compendium of useless information. I certainly can understand his plight with one of the seven having way too many questions and answers a

10、ll the time. On the positive side, I learned a new word that day when I looked up compendium in the dictionary.There were probably even indications that my curiosity might be scientific. Burlington Massachusetts was rural when I was young and I loved to roam and explore. I had rock collections and r

11、ead childrens books on geology and the history of the earth. I made little volcanoes out of plaster of paris and added baking soda and vinegar to the craters to simulate volcanic eruptions. I had an accident one day that made my mother laugh to my utter frustration: at that young age I failed to app

12、reciate the humor in a little boy telling his mother he had dropped a volcano on his toe! In the summer I collected butterflies, turtles, snakes and other living things. One summer my mother enrolled me in a science enrichment class for elementary school students and I was allowed to take home a mic

13、roscope. I used it to look at everything I could find: microorganisms from the nearby pond, leaves and blades of grass. I spent hour after hour alone, mesmerized by the tiny little things that I could see.,My scientific curiosity took a back seat to athletics through junior high and high school. Gym

14、nastics was a good match to my small build and to my solitary nature. I was a member of a team but gymnastics is an individual sport. You learn a technique, then a move, and then a routine. And then you perfect it through practice, working mostly alone. I had a very good no nonsense teacher, coach H

15、ayes, who really instilled in me the idea of perfection through practice. I was actually not all that bad, particularly at floor exercise and high bar. I even considered pursuing gymnastics in college, but during my final year of high school I began to wonder what I should pursue for a career.I atte

16、nded the University of Massachusetts in Boston for one year and then transferred to Brandeis University. Brandeis was an eye opening experience for me. For the first time in my life I was in a seriously intellectual environment. The classes tended to be small, intense, and stimulating. I discovered

17、that I had a passion for science, and that I was very good at it. I chose Biochemistry as a major and a newly arrived assistant professor named Chris Miller for my honors thesis advisor. He had a little laboratory with big windows and lots of light shining in. I studied calcium transport and learned

18、 about the cell membrane as an electrode. I could see that Chris Miller was a man having lots of fun in his daily life and it was inspiring to me, and the memory of this stayed with me. But the biggest influence Brandeis had on my life happened in Physics class. There I met my future wife Alice Lee,

19、 whose sparkling eyes and sharp mind caught my attention.Against Chris Millers advice I went to medical school after Brandeis. I studied at Tufts University School of Medicine and then at Beth Israel Hospital Boston for house officer training in Internal Medicine. I learned a lot but in the end I sh

20、ould have taken Chris advice to pursue science. Medicine required a lot of memorization and little analytical problem solving. To keep a certain part of my brain active I began to study mathematics, and continue this even today, learning new methods and solving problems with the same disciplined app

21、roach I had learned in gymnastics. I started back to science near the end of house officer training working with Jim Morgan studying calcium in cardiac muscle contractility, which was very enjoyable and kept me connected to medicine. But I had a yearning to work on a very basic science problem, whic

22、h meant I would have to break my medical ties. This was a difficult decision because I had invested so many years in medical education; to abandon it was to admit to myself that I had misspent a big piece of my life. And there were practical considerations as well. It was time finally to get a perma

23、nent job; after all, my wife Alice had supported me through years of training. Not to mention I was nearly 30 years old with no real basic science training beyond my Brandeis undergraduate education: would I even be able to make it as a scientist?,Two factors had the greatest influence on my decisio

24、n. Back in my first year of medical school I lost my sister Elley, an artist only two years my senior. Diagnosed with leukemia during my hematology clerkship as I learned about the dreaded disease, she lasted only two months. This horrifying event impressed upon me how fragile and precious life is,

25、and how important it is to seize the moment and enjoy what you do while you can. I remember thinking when I look back upon my life at the age of seventy, thirty will seem young: just go for it. And the second factor was Alice. She had complete faith in my ability to succeed. Never mind that postdoct

26、oral studies meant a reduction of my already piddling house officer salary. She simply said you have no choice; we will manage somehow.Memories of Chris Millers laboratory beckoned so I returned for postdoctoral studies. Of course I will never out live his reminding me that I should have listened to

27、 him in the first place. Feeling far behind in my knowledge I approached my postdoctoral studies with intensity, learning techniques and theory. I felt I should be an expert in electrochemistry, stochastic processes, linear systems theory, and many more subjects. I read books, solved the problem set

28、s, mastered the subjects, and carried out experiments. I had the very good fortune of a coworker Jacques Neyton, a postdoctoral scientist from France. Jacques is a very critical thinker who would brood on a problem. We exchanged ideas often. When I would tell him one of my ideas he had a tendency ju

29、st to listen quietly. Then, after a while, if his response started with Hey Roddy, theres something I dont understand I knew I was in trouble - my idea was probably no good!After I completed a series of biophysical studies on K+ channels it came time to apply for an academic position. During the lat

30、e 1980s physiology departments were more interested in hiring channel gene cloners than bio-physicists. But Peter Hess convinced his colleagues at Harvard that my work showed promise and I was offered an assistant professorship there. My laboratory made good progress on K+ channels. It was exciting

31、for a while but in just a few years I began to feel that the return on what we could learn from studying the functional effects of mutations was diminishing. We had identified the K+ channel signature sequence, but without knowing its structure we never would understand the chemical principles of io

32、n selectivity in K+ channels. I decided at that point to learn X-ray crystallography to someday see a K+ channel.,I began to learn methods of protein purification and X-ray crystallography while still at Harvard, initially working with channel toxins and a small soluble protein called a PDZ domain.

33、However, I thought it best to move away from my familiar environment at Harvard to pursue channel structure. There were really two reasons motivating me to move. First was the practical issue of obtaining funding to work in an area in which I had no background: start-up funds associated with moving

34、to a new university would be useful for this purpose. The second and far more important reason was that moving would enable me to immerse myself completely in the new endeavor. A change of environment would remove the distractions of everyday life, isolate me from the temptation to fall back on chan

35、nel physiology studies that I was already good at, and allow me to focus with singular purpose on the structural studies. I needed this to become an expert in membrane protein biochemistry and X-ray crystallography, and to develop a feel for protein structure. When the president of Rockefeller Unive

36、rsity Torsten Wiesel heard about my scientific plans he suggested that I move to Rockefeller University and I did. Rockefeller provided a wonderful environment for concentrating on a difficult problem.It has been said that giving up my already successful lab at Harvard in order to pursue the structu

37、re of a K+ channel was a risky thing to do. At the time I was told that my aspirations were altogether unrealistic. From my perspective I had little choice because I wanted to understand K+ selectivity and I knew that the atomic structure provided the only path to understanding. I would rather fail

38、trying than never try at all. It helped that I was accustomed to making transitions and had become good at teaching myself new subjects. I have to admit that few people working with me at the time wanted much to do with the new endeavor - only one new postdoctoral scientist Declan Doyle was enthusia

39、stic. My wife Alice, an organic chemist, saw that I was going to be pretty lonely and decided to join me in the lab. And to my good fortune she has worked with me since. I have learned that most people do not like change but I do. For me change is challenging, good for creativity, and it definitely

40、keeps life interesting.,I think of the past eight years of my life in New York at Rockefeller University as a personal odyssey. The new laboratory started out very small, with only Declan, Alice and me. But it grew in the first year with the addition of other enthusiastic postdoctoral scientists, in

41、cluding Joo Morais Cabral and John Imredy. Working with membrane proteins was very difficult as expected. We had our periods of despair, but every time we felt left without options something good happened and despair gave way to excitement. Persistence and dedication eventually paid off. The atomic

42、structure of the K+ selectivity filter was more informative and more beautiful than I ever could have imagined. My laboratory now is an incredible place, overflowing with excitement and ideas sustained by the continual infusion of bright young scientists who come from around the world to work with m

43、e. It gives me great satisfaction to know that these young scientists who are sophisticated in their knowledge of protein chemistry and structure will lead the field of ion channel research into the future. This has been a wonderful adventure. I owe thanks for the life I have: to Alice, to all my lo

44、ving family of MacKinnons and Lees, to my scientific family of students, postdocs and colleagues, to senior colleagues who have helped me along my way to pursue my passion, and to the Rockefeller University, the Howard Hughes Medical Institute, and the National Institutes of Health for their support

45、. I am very thankful for my life as a scientist, for the opportunity to understand in some small way the world around me. I hope my best experiment and scientific ideas are yet to come. This hope keeps me going.,http:/www.nobelprize.org/nobel_prizes/chemistry/laureates/2003/mackinnon.html,一、General

46、properties 1. Valence electron of alkali metals: (1)其氧化数为+1，不会有其它正氧化态。 在无水无氧条件下，可以制得低氧化态的非 寻常化合物。例如钠在乙二胺和甲胺中所形 成的溶液也具有导电性，观察到Na-的光谱 带，说明主要的导电体应是钠电离出的Na+ 和Na- 。,cryptand-222,Inverse sodium hydride,+ H2,(2) 由于价电子数少，所以碱金属原 子之间的作用力比绝大多数其他金属 原子之间的作用力要小，因此碱金属 很软，低熔沸点，且半径大、密度小。 Li的密度是所有金属中最小的，它的 密度比煤油小。,2.

47、 在形成化合物时，碱金属元素以离子键 结合为特征，但也呈现一定程度的共价性。 (1) 气态双原子分子Na2 、Cs2以共价键结合 (2) Li的一些化合物共价成份最大，从Li Cs的化合物，共价倾向减小。,(3) 某些碱金属的有机物，有共价特征。 例如Li4(CH3)4甲基锂,二、Lithium and its compounds 1. General properties:Li的性质与碱金属有很大区别，但与碱土金属，特别是Mg的化学性质相似，这种关系称为对角线关系（diagonal relationship）。 Li与碱金属元素（Na、K、Rb、Cs）的区别： (1) 锂的硬度比其它碱金属都

48、大，但与碱土金属相似。 (2) 锂形成正常氧化物，而不形成过氧、超氧化合物。 (3) 锂与氮气形成氮化物，其他碱金属不能与N2直接化合，而碱土金属与N2能直接化合。 (4) 只有锂与碳反应生成Li2C2（乙炔锂），碱土金属都能形成MC2。 (5) 三种锂盐（Li2CO3、Li3PO4和LiF）溶解度小，碱土金属这三种盐的溶解度也小。,二、Lithium and its compounds 1. General properties:6. 锂的有机金属化合物与镁的有机金属化合物相似7. 许多锂的盐有高度的共价性，与镁相似。 8. 锂的氢氧化物、碳酸盐加热（与Mg相似）分解成氧化物和水或二氧化碳

49、；其他碱金属的氢氧化物、碳酸盐加热难分解；而氢化锂加热不分解，氢化钠加热分解成氢气和气态Na2,C2H5MgBr,2. The simple substance (1) Lithium is a soft ,silvery white metal, the lightest of all metals (2) preparation: 电解LiCl(55%)KCl(45%) (3) 与非金属反应.加热时，它直接与S,C,H2反应 (4) 在空气中被氧化，生成Li2O和Li3N；在CO2中加强热，可以燃烧 (5)与金属反应，生成金属互化物,(6) 与H2O,H+剧烈反应，但在水中反应会减慢，由于

50、LiOH溶解度小 (7) 它是Tritium的来源3. 化合物 (1) Li的二元化合物的化学性质、溶解度和水解性与相应的Ca、Mg化合物相似 (2) LiF,Li2CO3,Li3PO4溶解度小 (3)LiOH = Li2O + H2O 这与其它碱不同，LiOH作为蓄电池的电解质,Heat,(4) 锂盐与相类似的其他碱金属盐形成 a. 低共熔混合物 LiNO3KNO3 LiNO3NaNO3KNO3 b. 复盐 M +LiSO4 Na3Li(SO4)2 6H2O (5) 过氧化物（peroxide）不是Li的特征 (6)Li的某些矿物和人造化合物可用来制备珐琅，特殊玻璃（透过紫外光）,Graph