Are All Chemical Bonds the Same

Chemists refer to the bond in a molecule like sodium chloride as ionic , meaning that its electron pair resides entirely on chlorine. At the other extreme is the covalent bond in the hydrogen molecule, where the electron pair is shared equally between the two hydrogens. Intermediate cases, such as the bond in hydrogen fluoride which is clearly polarized toward fluorine, are generally referred to as polar covalent bonds (rather than partially ionic bonds). Are these situations really all different or do they instead represent different degrees of the same thing  

examine electrostatic potential maps for the same set of compounds. Focus your attention on the value of the potential around hydrogen. For which molecule is it most positive For which is it most negative Is there a correlation between the value of the potential and the difference in electronegativities Plot charge on hydrogen (vertical axis) vs. difference in electronegativities (horizontal axis). Is there a correlation  

What electronegativity difference, large or small, creates a more polar bond A more covalent bond  

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Besides the discovery of new peptides, the routine investigation of peptide influence and metabolism requires a separations-based techifique. Biologically active peptides are numerous. They are all synthesized in the same general way. Transcription and translation leads to prepropeptides [3]. These proteins may be the source of several different active peptides. Specific enzymes are nsed to create first the propeptide and then active peptides. Active peptides are then inactivated, usually by a peptidase that hydrolyses an amide bond in the peptide [4]. It is therefore certain that a large number of different molecules share the same primary sequence, and it is likely that a large number of molecules may cross-react with a peptide-reactive antibody. Thus, any immunoassay is bedeviled by selectivity issues. If a perfectly selective antibody were available, it would be useful. However, it is undeniable that ultimately a complete understanding of, for example, the action of peptides in the brain [3-5] will only come about when the dynamics of all of the relevant processes are understood. This can only be done with chemical analytical techniques that can track the concentrations of all of the peptides relevant to a particular process. 

Like the denizens of the plant and animal kingdoms, plastics fall into distinguishable genera. The main subdivisions are thermoplastics and duroplastics. Thermoplastics are those that soften when heated, and so can be formed into the desired shapes, to harden again when cooled. They make up the greater part of the products of the plastics industry, and include predominantly polyethylene, polypropylene, polystyrene, and polyvinyl chloride (PVC). They are not cross-linked (or only very sparsely so), and they are all synthesized by the same type of chemical reaction, for all are made from monomers with carbon-carbon double bonds, which open up to create a chain. (This is not a universal rule, though some of the less familiar thermoplastics are made by different routes.)... 

The reader s attention is drawn to the discussion in Sections 14.3 and 14.4 which shows that all chemical bond models are equivalent because they all reduce to this same topological description. The derivation here is based on the ionic model because it is the simplest and most convincing. 

The adsorption capacity of various solids for a specific gas depends primarily upon the effective area of the solids. For a series of gases, the order of increasing adsorption is the same for all solid adsorbents. These similarities hold as long as there are no chemical bonding factors intervening in the adsorption process. Gases that are the most easily liquified are the most readily adsorbed at a solid surface. Table 2.2 depicts data for the adsorption of a number of gases on 1 g of activated charcoal at 15°C(1). 

These formulas are equivalent in that the same number of bonds are shown and the same general planar geometry would be predicted, but in each one a different oxygen atom is double bonded. There is really no basis for thinking that one of these formulas is a better representation for nitrate ion than the other. In fact, neither formula is adequate because all the oxygen atoms are chemically equivalent in... 

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