离子极化与化合物的颜色

针对现行《无机化学》统编教材讨论“离子极化与化合物颜色的关系”时存在的一些问题,作了初步探讨,阐述了术语“颜色深浅”的含义,提出了用离子极化观点解释物质颜色时应注意的问题.     

离子极化理论及其应用

用离子键理论不能解释离子化合物的某些性质。本文首先简单介绍了离子极化理论,然后用该理论对无机物的颜色、溶解度、离子晶体的晶型及熔沸点,盐的水解度,二元化合物稳定性,含氧酸的酸性,配合物的稳定性等性质进行解释。     

初探无机化合物的颜色

在无机化学中,尤其在过渡金属元素配合物中经常会遇到各种各样颜色的无机化合物。具有dx(x=1至9)结构的过渡金属配合物受到光照时,d轨道跃迁,发生d-d跃迁。化合物吸收可见光还可以发生电子从一个原子到另一个原子的跃迁而产生荷移吸收带发生电荷跃迁。酸根和固体化合物的颜色就与电荷跃迁有关。此外,离子极化作用也可以使物质具有颜色。对无机化合物显色规律、原因作了详细的总结,并对其显色机理做了深刻的探讨。     

“离子对应”的妙用

在初中化学的学习中，学生对于推断题及有关除杂质的题目，在解答上普遍存在着困难。解答过程中会出现或多或少的问题，或不准确，或无从着手，逐渐地，大部分学生将这一类题目视为难题而放弃。经过多年的教学总结，我发现，在人教版九年级化学下册第十、第十一单元中有许多离子对应关系，对于解答这一类题目女小有帮助。所谓离子对应关系，就是这些离子对应的化合物在相互作用后能产生特殊的、明显的实验现象。己知加入的离子对应的化合物，结合题目中给出的实验现象，结合酸、碱、盐的化学性质及溶解性表，可以初步确定物质的范围和除杂质所需要的物质。最终，推断出相对应的未知离子所对应的化合物。小结如下表：     

电离平衡难点透析

一、电解质是离子化合物还是共价化合物的判断 电解质导电属于离子导电。在水溶液中，不管是离子化合物还是共价化合物，都电离产生能自由移动的离子，因此在水溶液中，可溶性的离子化合物和共价化合物都能导电。但在熔化状态下，离子化合物能电离出自由移动的阴、阳离子，而共价化合物仍以分子的形式存在，因而共价化合物不能导电。从而得出判断离子化合物和共价化物的方法：在熔融状态下做导电性实验，能导电的为离子化合物，不能导电的为共价化合物。     

“核外电子排布的初步知识”学习要点

核外电子排布的初步知识是初中化学物质结构理论的重要内容之一．是学习化合价及今后学习元素化学性质、离子化合物、共价化合物的理论依据。要学好这一部分知识，应掌握以下几个要点：     

判断水溶液中离子不能大量共存的依据

如果试题已指明溶液无色，则有色离子不能大量共存。常见呈现颜色的离子有：外壳电子数为9～17的第一过渡系元素的水合离子，能吸收一定波长的可见光，使其离子由基态跃迁到激发态，而呈现颜色。这些离子的颜色列于表1。     

再谈物质结构决定物质的性质

前面借贵刊浅谈了物质的结构决定物质性质的一些问题,今天再来谈一下与酸、碱、盐相关的物质结构决定物质性质的内容。酸、碱、盐属于不同类别的化合物,在初中化学中从电离的角度给这三类化合物下了定义,我们就从电离出来的相同结构的离子谈起。     

二价铜离子在分析化学中的应用

铜(Ⅱ)离子的外层电子构型为3S^23P^63d^9。它的3d，4S、4P电子亚层有能级较低的空轨道．可以接受N、O、S等原子所提供的孤电子对，而形成共价型或配位型极性键的化合物，且有特征的颜色。据此，可以利用某些有机试剂对二价铜离子进行鉴定和含量测定。     

常见金属元素——铝

1 铝及其化合物的知识网络 2 知识重点及考点分析 铝是金属元素中比较特殊的一种,铝及氧化铝既能与酸反应,又能与碱反应.Al2O3是典型的两性氧化物,Al（OH）3是典型的两性氢氧化物,除此之外,Al（OH）3溶液还是胶体（净化原理）.正是由于铝及其化合物的这种特殊性质,所以高考对铝的考查几乎都涉及这3种物质,并且出题以离子共存、离子方程式的判断,物质的鉴别,还有溶解平衡等多种方式.     

瓯语复合色彩词与比喻造词简

瓯语复合色彩词的类型主要有单合复合色彩词和多合复合色彩词.单合复合色彩词包括联合式和偏正式;多合复合色彩词包括异构偏正式和同构偏正式.瓯语复合色彩词中比喻构词的种类主要是明喻构词和借喻构词两种.     

Attention shifts during matching-to-sample performance in pigeons

Two pigeons performed a matching-to-sample task in which a color, a line orientation, or both, might appear on the sample. Stimulus control by (attention to) the color and line components of a compound sample was measured when (a) either component might be relevant (i.e., appear as a comparison stimulus on that trial), and (b) when only one component was relevant. Degree of stimulus control by a given component of the compound sample was higher when only it was relevant than when either component might be relevant. Because the matching-to-sample task separated sample inspection from response choice, interpretation of the results in terms of response competition was ruled out. Because the training procedure led to shifts in stimulus control by the components of the compound sample, explanation of previous matching-to-sample results in terms of reduced perceptual clarity of compound samples was also ruled out. Thus, variations in stimulus control by components of the compound sample were interpreted as showing shifts in attention to the components of the compound sample.     

Extinction of stimulus elements decreases the rate of conditional discrimination learning

Pigeons were trained on a successive discrete-trial conditional discrimination, in which either of two colors appeared on the center key and either of two forms appeared on the two side keys. Some combinations of color and form (S+ trials) were followed by food; other combinations (S-trials) were followed by no food. The colors on the center key appeared throughout the intertrial interval (ITI) preceding the trial period in which both the color and the form compound were presented or the color appeared only during the trial period in compound with the forms. Presentation of the colors during the ITI substantially degraded acquisition of two separate types of conditional discrimination. The results show that the temporal correlation of the eolors-with food, independent of their association with the form cues, played a substantial role in determining their availability for acquisition of the conditional discrimination.     

Pauling规则解释化合物活性、稳定性

由于Pauling规则实质上体现、规定了使离子晶体结构处于最低位能和具有高稳定性的条件，所以它能对化合物稳定以适当的量度。本文结合实例说明了Pauling规则在联系化合物稳定性、生物化学活性方面的应用。     

Spatial and configural factors in compound stimulus processing by pigeons

Three matching-to-sample experiments examined whether spatial or configural factors determined how the element arrangement of compound sample stimuli influenced matching accuracy in pigeons. Seven types of compound stimuli were tested. The arrangement of color and line-orientation elements in these compounds varied in terms of the spatial separation between the elements, the degree of consistency in element spatial location, and the number of bounded areas containing the elements. Matching accuracy was examined upon initial exposure to the compounds, during asymptotic conditions of shared attention, and with variation of sample durations ranging from .04 to 5.935 sec. In all three experiments, when spatial proximity, locational certainty, and the number of lines were precisely controlled or equated, no evidence for the proposed configural processing of “unified” compounds was found (Lamb & Riley, 1981). Element spatial separation, and to a lesser degree perceptual limitations, determined compound performance. These results question our lab’s previous evidence for configural compound processing by pigeons (Lamb, 1988; Lamb & Riley, 1981). They suggest instead that pigeons independently and separately process the individual elements of color/line-orientation compounds, with element separation determining the distribution of processing between the elements.     

[Fe(CN)_6·(PhCH_2NC_9H_7)_4·KCl·H_2O]·5H_2O的合成、晶体结构及电化学性质

合成了一个新的离子型化合物[Fe(CN)6.(PhCH2NC9H7)4.KCl.H2O].5H2O。经红外光谱、元素分析及X-射线衍射对其结构进行了表征,并采用循环伏安法研究了它的电化学性质。化合物晶体属三斜晶系,P1空间群,晶胞参数:a=11.068(7),b=11.139(7),c=14.837(9),α=76.724(8)°,β=81.499(8)°,γ=68.537(7)°,V=1652.9(17)3,Mr=1275.74,Z=1,Dc=1.282Mg.m-3,F(000)=668,吸收系数μ=0.391mm-1,最终偏离因子R1=0.0623,wR2=0.1582。化合物的基本单元是由4个(PhCH2N+C9H7)离子、一个[Fe(CN)6]4-离子、一个水合氯化钾分子及5个水分子组成。由结构分析结果可知,[Fe(CN)6]4-通过氢键相互联接,而(PhCH2N+C9H7)和[Fe(CN)6]4-离子是靠静电引力结合在一起的。     

核桃仁黑芝麻复合保健半固态饮料的研制

以核桃仁、黑芝麻为主要原料 ,经科学加工处理后 ,添加何首乌汁 ,糖浆、蜂蜜等辅料 ,经调配、灭菌、包装等工序加工而成的核桃仁黑芝麻复合保健半固态饮料 ,其色泽乌黑 ,香甜可口 ,营养丰富 ,风味独特 ,具有很强的保健作用     

Two perceptual variables in within-event learning

Four autoshaping experiments employed pigeon subjects to explore within-stimulus learning. Experiments 1 and 2 investigated the formation of an association between two elements within a visual compound as a function of the similarity of the elements to each other. As in earlier experiments on the formation of associations between stimuli, similarity improved learning within a stimulus. Experiments 3 and 4 examined the formation of color-form associations when the color was a property of the form or of the ground on which the form occurred. Learning was better between the form and its color than between the form and the color of its background. These results suggest that perceptual variables contribute to within-stimulus learning.     

关于佛经文献《贤愚经》中“颜色”“妻子”等词语演变的分析

文章通过对佛经文献《贤愚经》中的“颜色”“妻子”等这类古今常用意义上差异很大,古代时充当的是一个词组而今天凝固成了一个不可分的合成词的词语进行分析,阐释了为什么会发生这类变化,借助辞书等寻找本词语的演变过程及演变的作用。