Degree of ionicity

In conclusion it appears that the indole magnesium halides are essentially N—MgX species, with the degree of ionic character of the N—MgX bond being markedly affected by external factors, such as... 

The influence of Ca2+ on the variations of adsorption with the degree of ionicity of HPAM on sand at pH 7 in 2 g/1 NaCl is given in Figure 9. Without calcium, adsorption decreases with polymer charge because of the increase in... 

Similar reactions occur with all aliphatic halides and the rates of substitution are related to the degree of ionic character of the carbon-halogen bond. For preparation purposes, trityl bromide or propargyl bromide are more convenient than allyl bromide. The compounds obtained are listed in Table XI. They were obtained pure and characterized fully. Zr (allyl) 3Br and Zr(allyl)2Br2 are sufficiently soluble in toluene for polymerizations to be initially homogeneous. Their relative reactivities are listed in Table XI. In all cases hydrogen was used to reduce the molecular weight of the polymer formed. In this respect the polymer derived from Zr (allyl )3Br was more readily modified than that from Zr (allyl) 4, but in order to avoid... 

Recently, a deeper understanding of the precise nature of metal-carbon bonding was achieved, enabling specific polymerization catalyst systems to be designed on a practical level. The metal-carbon bond of early transition metals is partially ionic, while that of late transition metal is generally covalent. The degree of ionicity is delicately dependent on the identity of metal, formal oxidation states and auxiliary ligands. 

H2S, hydrogen sulfide, is the product of hydrogen gas reacting with a nonmetal, sulfur. A compound consisting of two nonmetals is primarily covalent, and has a much smaller degree of ionic character. 

Degree, of Ionic Nature in Solid Rare Earth Compounds... 

These results may at first seem somewhat surprising, for since it can be deduced that a more negative isomer shift corresponds to decreasing s electron density at the nucleus, within each valence group this implies an increasing degree of ionic nature. Indeed, the more positive shift for... 

Based on the controversies outlined above, discussion on the degree of ionicity in natural silicates appears highly conjectural and superfluous, because there is no agreement even for building group [Si04]. Therefore, no mention will be made hereafter of the degree of ionicity (or covalence) in these compounds. 

When there is a considerable difference in the electronegativities of two elements, the bond is said to be polar, that is to say there is a high degree of ionic character. This the case with salts such as sodium chloride. However, in the majority of bonds the sharing of the electron pair is not exactly equal and the bond is said to have partial ionic character. 

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