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1.
本文通过条件选择合成两种Co(Ⅲ)配合物键合异构体[Co(NH3)5NO2]Cl2(配合物1)与[Co(NH3)5ONO]Cl2(配合物2),通过红外光谱、紫外光谱对配合物进行表征。确立两种键合异构体可能的结构。  相似文献   

2.
探讨了在酸性介质中用H2O2或盐酸羟胺做还原剂,把Co(Ⅲ)还原为Co(Ⅱ),采用配位滴定法测定配合物Co(NH3)6Cl3中的钴含量可获得满意的效果.  相似文献   

3.
本文通过条件选择合成两种Co(Ⅲ)配合物键合异构体[Co(NH3)5NO2]Cl2(配合物1)与[Co(NH3)50NO]Cl2(配合物2),通过红外光谱、紫外光谱对配合物进行表征。确立两种键合异构体可能的结构。  相似文献   

4.
铵盐与强碱的稀溶液之间混合反应时没有氨产生,这是公认的事实·其原因是生成的新碱(NH3·H2O)产生的氨在水中的溶解度特别大,常温常压时1体积水中可溶解约700体积的氨;生成的新盐(钠盐、钾盐)多为易溶物·其反应的离子方程式为:NH4 OH-NH3·H2O但浓的铵盐溶液与浓的强碱溶液之间在通常情况下混合反应时是否有氨产生和有晶体析出呢?高三新教材第32页有这样一段叙述:如果把(NH4)2SO4浓溶液和NaOH浓溶液混合时,生成挥发性的NH3……反应可用离子方程式表示:NH4 OH-=NH3↑ H2O这种表示意味着浓的铵盐与浓的强碱之间反应时有氨产生…  相似文献   

5.
从实验和理论两个方面进行探讨,说明了制备铜氨配合物晶体的试剂浓度和试剂用量的关系,用硫酸铜溶液所制备的铜氨配合物晶体的成分不单只是[Cu(NH3)4]SO4·H2O,而是[Cu(NH3)4]SO4·H2O与[Cu(NH3)4](OH)2·nH2O的混合物。  相似文献   

6.
化学教材上均认为银氨溶液的成分是[Ag (NH3 ) 2 ]OH (氢氧化二氨合银 ) ,这是值得商榷的。1 银氨溶液的成分是什么教材上银氨溶液的配制为 :在洁净的试管里加入 1mL2 %AgNO3 溶液 ,然后一边摇动试管 ,一边逐滴滴入 2 %的稀氨水 ,直到最初产生的沉淀恰好溶解为止 (这时得到的溶液叫做银氨溶液 )。发生的一系列反应为 :       生成沉淀的离子方程式 :Ag+ +NH3 ·H2 O→AgOH↓ +NH+ 4①沉淀溶解的离子方程式 :AgOH + 2NH3 ·H2 O→ [Ag (NH3 ) 2 ]++OH-+ 2H2 O②  由于反应①生成的NH+ 4与反应②生成的OH-结合生成N…  相似文献   

7.
论述了在配合物中水分子形成氢键的4种形式:结晶水分子与周围原子形成了四面体型的氢键;结晶水分子通过氢键形成水簇;结晶水与配体形成的氢键;配体水分子和其他配体之间的氢键。并分别以配合物[Cu3(μ2-Hdatrz)4(μ2-Cl)2(H2O)2Cl2]·Cl2·4H2O·2C2H5OH(Hdatrz=3,5-二氨-1,2,4-三唑),[Co3(μ2-Hdatrz)6(H2O)6]·(NO3)8·4H2O,{[Zn2(μ2-SO4)(μ3-datrz)2]}·2H2O}n,[Mn(Cl Phtrz)(SO4)(H2O)2]n(Cl Phtrz=4-(4-氯苯基亚甲基)亚胺-1,2,4-三唑希夫碱)为例,对4种形式的氢键的形成及其在配合物超分子结构中所起的作用做了梳理。  相似文献   

8.
众所周知,Cu(NO3)2溶液呈蓝色,但Cu和浓HNO3反应后残留液颜色却为绿色,而Cu和Cl2反应生成CuCl2,其水溶液的颜色浓时也呈绿色,稀时呈蓝色。课本中只给出了CuCl2溶液颜色随其浓度的改变而改变这一解释,而且此知识在教师用书及高等无机教材中均有详细说明。但对于Cu和浓HNO3反应后的溶液为何呈绿色?在课本、教师用书及相关资料中都没有作说明,这样给中学老师在教学过程中带来诸多不便,本文通过相关实验就此问题作一探讨,与老师们共同研讨和商榷。  相似文献   

9.
巨信息题丑已知氨合H+和Ag千的能力,前者显著强于后者,要使[Ag(NH3)2]+转化为自由的Ag+,其有效的试剂是,实现这一转化的离子方程式是 解析:(1)H+能夺取〔Ag(NH。)2]+中的NH。生成更稳定的NH4+。(2)NH;+比〔Ag(NH3)2]+更难释放出NH:。如所加试剂必须是酸,而且试剂中阴离子不能与Ag+结合,故有效试剂是硝酸,离子方程式为:〔Ag(NH3):」++ZH+一Ag十+ZNH;+。 〔延伸题〕向银氦溶液中加入NaCI溶液无白色沉淀生成,说明溶液中无_存在或存在较少,但加入盐酸后立即产生白色沉淀,有关反应方程式为_。 解析:加入盐酸后,H十与〔Ag(NH3):]…  相似文献   

10.
在研究和应用配合物时 ,首先要考虑它的稳定性 ,如热稳定性、溶液中的稳定性、氧化还原稳定性等等。其中应用最广泛的是配合物在溶液中的稳定性 ,这种稳定性一般用配合物在溶液中的稳定常数来衡量。以 Ag 与 NH3 的配合物反应为例Ag NH3 [Ag (NH3) ] R1 =[Ag (NH3) ] [Ag ] [NH3] =1 0 3.2 7[Ag (NH3) ] NH3 [Ag (NH3) 2 ] R2 =[Ag (NH3) 2 ] [Ag ] [NH3] =1 0 3.96该反应的总稳定常数 K=R1 R2 =1 0 7.2 3 .稳定常数的大小 ,直接反映了配离子稳定性的大小。对于相同类型的配离子 ,可以用 K稳 来比较其稳定性。如 …  相似文献   

11.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

12.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

13.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

14.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

15.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

16.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

17.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

18.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

19.
现在,我们可以没有面包,没有钱,没有房子,没有车子……但我们唯独不能丢失的是高尚的情操,笃定的信念,还有,满满的希望!  相似文献   

20.
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator's Garden. Translating building data to the Virtual Reality Modeling Language (VRML) is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching.  相似文献   

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