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在无机化学实验"三氯化六氨合钴(Ⅲ)的制备及组分测定"中,产物合成产率较低,影响后续实验开展和教学效果。本文基于基本化学原理优化实验合成条件,考查了活性炭催化剂用量、粒度和盐酸用量对三氯化六氨合钴(Ⅲ)产率的影响。实验结果表明:当活性炭催化剂用量为0.2 g、粒度为120目、盐酸溶液为(25 mL热水+1 mL盐酸)、浓盐酸用量为3 mL时,三氯化六氨合钴(Ⅲ)产率可达到42.5%,产品颜色(橙色)、纯度和结晶度明显提高,达到了实验预期结果。并且对不同粒度的催化剂,确定了可靠活性炭用量。通过该实验提高了学生化学基本原理的应用能力和解决问题能力。 相似文献
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六氨合钴离子交换法测定粘土中阳离子交换容量 总被引:6,自引:0,他引:6
六氨合钴离子「Co(NH3)6」^3+具有与粘土中主要阳离子(Ca^2+、Mg^2+、K^+、Na^+、H^+等)交换的能力。稳定性好,并在474nm处有最大吸收。利用分光光度法,以「Co(NH3)6」^3+作为交换离子,测定阳离子交换容量。试验表明,在PH7-8,常温条件下7h交换达到平衡;在80℃时3h可以达到平衡。粘土中共生的非粘土矿物、游离金离离子不干扰其测定。用该法测得的阳离子交换容量值与氯化铵溶液法,盐基分是测定法测得的结果一致。 相似文献
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介绍一个综合化学实验,主要内容为用三氯化铁和草酸钾为原料水相制备三草酸合铁(Ⅲ)酸钾并对其结构进行表征。测定了配合物的组成和配离子电荷,重点研究了配体和配合物的电子光谱和红外光谱,测定了配合物的磁矩、XRD和热稳定性等。实验结果表明,制得的配合物组成为K3[Fe(C2O4)3]·3H2O,产率90.0%;电子光谱吸收峰数值小于350~400 nm,是由配体到中心离子的电子跃迁产生的;红外光谱归属推断配合物中存在双齿或螯合的草酸根;配合物磁矩为5.16 B.M.,中心离子Fe3+的杂化态为sp3d2,配合物为高自旋的外轨配合物,八面体结构。通过该实验,学生能够理解配合物制备、组成测定和结构表征系列实验的原理,熟悉各种现代测试技术,激发学生对科学研究的兴趣,培养学生综合实验能力和创新能力。 相似文献
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三(3-羟基黄酮)合铝(Ⅲ)的合成及晶体结构 总被引:3,自引:0,他引:3
合成了三(3-羟基黄酮)合铝(Ⅲ),制得[Al(C15H9O3)3]2·2CHCl3·8H2O晶体,X射线衍射结果表明:其结构属于三方晶系,空间群为R3.晶胞参数:a=b=1.6558(3)nm,c=3.6465(20)nm,α=β=90°,γ=120°,V=8.65608(0.00586)nm3,Dc=1.45g/cm3,μ(MoKα)=3.20cm-1,F(000)=3924.分子中每个3-羟基黄酮以其独特的酮基和羟基同时与Al3+配位,3个配体中的6个配位氧原子形成扭曲的配位八面体. 相似文献
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顺式-二(乙二胺)二硝基合钴(Ⅲ)苹果酸盐的晶体结构及手性识别 总被引:2,自引:1,他引:2
合成了标题化合物,并用X-射线衍射法确定了该分子的晶体结构。化合物Δ(λλ),Λ(δδ)-cis-[Co(en)2(NO2)2]2d,l-C4H4O5,Co2C12N12O13H22,Mr=657.94.晶体属单斜晶系,空间群为P21/c,晶胞参数:a=13.969(4),b=6.440(1),c=14.408(4)A,β=94.37(1)°,V=1292.3A3,Z=2,Dc=1.69g/cm3,μ=105.833cm-1,F(000)=668.最终偏离因子R=0.066,Rw=0.085。结构分析表明晶体存在无序现象,其阴离子C4H4O52-有两种排列方式。R-构型和S-构型的几率各为50%,手性识别是通过Δ构型的阳离子与阴离子R-构型C原子上羟基氧形成氢键相互作用;Λ构型的阳离子与阴离子S-构型C原子上羟基氧形成氢键相互作用而实现的。 相似文献
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A simple and efficient method for the convenient synthesis of 2-arylbenzimidazole has been described on reaction with o-phenylenediamine and various aromatic aldehydes using cobalt(II) chloride hexahydrate as a catalyst. The method is cost-effective, high-yielding, clean, and selective. 相似文献
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1 INTRODUCTION Widespread interest of metal-organic coordination compounds has been stirred by their intriguing struc- tural topologies and promising properties[1]. Al- though structural motifs of coordination compounds are mainly defined by metal ions’ coordination pre- ferences and chemical structures of organic ligands including the molecular angle, length and relative orientation of the donor groups[2], numerous other factors such as solvent systems, concentration, coun- terions and e… 相似文献
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Francesco Malatesta 《Journal of solution chemistry》2002,31(7):547-558
Activity coefficients of [Co(en)3](NO3)3 and [Co(en)3](ClO4)3, to be compared with [Co(en)3]Cl3 and the corresponding lanthanum salts previously studied, are determined. [Co(en)3]Cl3 data are revised. Ion interaction strengths vary in the same order found for La3+, i.e., as if nitrate and perchlorate ions were of smaller and larger size, respectively, than chloride ions; however, the differences are much smaller than in lanthanum salts. Tris(ethylenediamine)cobalt III and lanthanum nitrate, chloride, and perchlorate—like the corresponding hexacyanoferrate(III) and hexacyanocobaltate(III) salts, but contrary to sulfate salts—behave as if [Co(en)3]3+ were smaller in size than La3+. In the dilute regions, [Co(en)3](NO3)3 displays negative deviations from the limiting slope, a kind of behavior typical for 2:2, 2:3, 3:2, and 3:3 electrolytes, but unnoticed earlier for 3:1 or 1:3 electrolytes. Pitzer's equation parameters able to provide accurate activity and osmotic coefficients for [Co(en)3](NO3)3, [Co(en)3](ClO4)3, and, revised, [Co(en)3]Cl3 are reported. 相似文献
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Jindou Yang Mi Sook Seo Kyung Ha Kim Yong‐Min Lee Shunichi Fukuzumi Jason Shearer Wonwoo Nam 《Angewandte Chemie (International ed. in English)》2020,59(32):13581-13585
A mononuclear nonheme cobalt(III) iodosylbenzene complex, [CoIII(TQA)(OIPh)(OH)]2+ ( 1 ), is synthesized and characterized structurally and spectroscopically. While 1 is a sluggish oxidant in oxidation reactions, it becomes a competent oxidant in oxygen atom transfer reactions, such as olefin epoxidation, in the presence of a small amount of proton. More interestingly, 1 shows a nucleophilic reactivity in aldehyde deformylation reaction, demonstrating that 1 has an amphoteric reactivity. Another interesting observation is that 1 can be used as an oxygen atom donor in the generation of high‐valent metal‐oxo complexes. To our knowledge, we present the first crystal structure of a CoIII iodosylbenzene complex and the unprecedented reactivity of metal‐iodosylarene adduct. 相似文献
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Anthony Fucaloro Andrew Zanella Shierley Widjaja Jesslyne Widjaja 《Journal of solution chemistry》2005,34(12):1357-1370
Both the partial molar volumes (V∘solute) and refractions (R∘solute) of the solute at infinite dilution have been determined for a series of four octahedral N6-coordinated cobalt(III) species with increasing ligand size (ammonia, ethylenediamine, sepulchrate, and 1,2-diaminocyclohexane).
The experimental values for V∘ solute are consistent with the relative sizes of the ligands but show larger values than those generated by computer modeling as
the size of the cation increases. This suggests that the void space of the cation increases with the size of the cation. It
is proposed that increasing hydrophobicity of the alkane ligand frameworks contributes to larger volumes. 相似文献
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CoCl2·6H2O催化合成3,4-二氢嘧啶-2-酮衍生物 总被引:4,自引:0,他引:4
3 ,4 二氢嘧啶 2 酮类化合物可用作钙拮抗剂、降压剂、α1a 拮抗物等而成为近年来生物活性有机杂环化合物研究的热点之一[1 ] 。通常该类化合物是用Bigineli[2 ,3] 反应得到的。为了提高其产率 ,人们作了大量的研究工作[4,1 1 ] 。本文利用Co Cl2 6H2 O作催化剂 ,乙醇作溶剂 ,乙酰乙酸乙酯、芳香醛和脲一锅煮合成 3,4 二氢嘧啶 2 酮 ,同时考查了芳香醛的取代基及乙酰丙酮对产物收率的影响。反应方程式如下 :1 实验部分1 1 仪器与试剂熔点用毛细管法测定 ,温度计未校正。E QUINOX5 5红外光谱仪 (KBr压片 ) ;… 相似文献