氢、碱金属和碱土金属课件.ppt

1、 氢、碱金属和碱土金属 Hydrogen,Alkali and Alkali-earth metals1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 H)(T H)(D H33221OD OH SD OD SH T C n N T He n Li T He T 12.6Tritium nPreparatio

2、)3(222223112610143314210633231也可以用电解法来富集原理来获得纯重水例如：得通常只有核反应才能获放射性衰变体。年的是半衰期为）（制备(2)存在：H:D=6800:1(原子个数)H:T=1e10:1HeatCool (4)氢同位素形成的单质H2、D2、T2,在化学性质上完全相同，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

3、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=2HF c.还原反应：CuO+H2=Cu+H2O WO3+3H2=W+3H2O 1 3.Preparation (1)实验室：(2)工业上：2322242222-22222H SiONa OH 2NaOH Si 在野外工作)3(H C CH 烃裂解c.CO(g)(g)H OHC 水煤气法b.O2H O 4e-4OH 2OH H 2e O2H )中OH

4、(电解a.H Zn 2H Zn 应时利用硅的两性和碱反二、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.htmlSi(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 Potassium Li Na K Rubidium Cesium Francium Rb Cs Frfor structural and me

5、chanistic studies of ion channels Roderick MacKinnon The Nobel Prize in Chemistry 2003Peter Agre,Roderick MacKinnonK+channelI was born on February 19,1956 in the middle of a snowstorm.It remains one of those humorous family stories that my mother likes to tell.My father the planner had rehearsed the

6、 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 computers and became a programmer on the big IBM main frames.My mother worked as

7、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 expectations clear to us.Television is bad for you,reading is good for you,and you

8、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 the scientist.I suppose there were some early indications of my tendency to a life of curio

9、sity.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 give explanations to those around me,apparently to an annoying degree sometimes.I remember one da

10、y 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 all the time.On the positive side,I learned a new word that day when I looked up compendium in the di

11、ctionary.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 read childrens books on geology and the history of the earth.I made little volcanoes out of plaster of pa

12、ris 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 appreciate the humor in a little boy telling his mother he had dropped a volcano on his toe!In the summer I co

13、llected 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 microscope.I used it to look at everything I could find:microorganisms from the nearby pond,leaves and blades of g

14、rass.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.Gymnastics was a good match to my small build and to my solitary nature.I was a member of a team but gymnastics is an ind

15、ividual 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 Hayes,who really instilled in me the idea of perfection through practice.I was actually not all that bad,particularly at floor

16、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 attended the University of Massachusetts in Boston for one year and then transferred to Brandeis University.Brandeis was an eye opening

17、 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 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 n

18、amed 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 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

19、 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,whose sparkling eyes and sharp mind caught my attention.Against Chris Millers advice I went to medical school after Brandeis.I studied at Tufts U

20、niversity 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 should have taken Chris advice to pursue science.Medicine required a lot of memorization and little analytical problem solving.To keep a certain part

21、of my brain active I began to study mathematics,and continue this even today,learning new methods and solving problems with the same disciplined approach 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 m

22、uscle contractility,which was very enjoyable and kept me connected to medicine.But I had a yearning to work on a very basic science problem,which 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 a

23、dmit 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 permanent 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

24、my Brandeis undergraduate education:would I even be able to make it as a scientist?Two factors had the greatest influence on my decision.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 learn

25、ed about the dreaded disease,she lasted only two months.This horrifying event impressed upon me how fragile and precious life is,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 yo

26、ung:just go for it.And the second factor was Alice.She had complete faith in my ability to succeed.Never mind that postdoctoral 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 beckone

27、d so I returned for postdoctoral studies.Of course I will never out live his reminding me that I should have listened to 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 electr

28、ochemistry,stochastic processes,linear systems theory,and many more subjects.I read books,solved the problem sets,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 wou

29、ld brood on a problem.We exchanged ideas often.When I would tell him one of my ideas he had a tendency just 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 o

30、f biophysical studies on K+channels it came time to apply for an academic position.During the late 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

31、assistant professorship there.My laboratory made good progress on K+channels.It was exciting 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

32、,but without knowing its structure we never would understand the chemical principles of ion 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,in

33、itially working with channel toxins and a small soluble protein called a PDZ domain.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 wor

34、k in an area in which I had no background:start-up funds associated with moving 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 dist

35、ractions of everyday life,isolate me from the temptation to fall back on channel 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 dev

36、elop a feel for protein structure.When the president of Rockefeller University 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 givin

37、g up my already successful lab at Harvard in order to pursue the structure 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 str

38、ucture provided the only path to understanding.I would rather fail 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 endeavo

39、r-only one new postdoctoral scientist Declan Doyle was enthusiastic.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 chang

40、e is challenging,good for creativity,and it definitely 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

41、 of other enthusiastic postdoctoral scientists,including 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 an

42、d dedication eventually paid off.The atomic 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

43、come from around the world to work with me.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 t

44、he life I have:to Alice,to all my loving 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 Institut

45、es of Health for their support.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/

46、mackinnon.html 一、General 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-。NaNaNa223NHCHen 2Na(s)+C20H36O6Na(C20H36O6)+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

47、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.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 3.05VE)hydration of enthalpy(Li*2.91-2.74-2.61-2.43-2.1-M eM2.92-2.93-2.92-2.71-3.05-M e MCs Rb K Na Li E 3.

48、(sol)/LiLi(met)-*(sol)-/MM使得离子的水合焓高这是由于二、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

49、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；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 2Li(s)+C4H9Cl612C H LiC4H9+LiCl(s),C2H5Br+Mgether C2H5BrMg C2H5MgBr 2.T

50、he 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,Li