Electronegativity acid strength

Indolmycin, biosynthesis of, 864 Inductive effect. 37, 562 alcohol acidity and. 604 carboxylic acid strength and. 758 electronegativity and, 37 electrophilic aromatic substitution and, 562... 

Strategy The structure can be obtained by removing an oxygen atom from H O, (Figure 21.8). Relative acid strengths can be predicted on the basis of the electronegativity and oxidation number of the central nonmetal atom, following the rules cited above. 

As electronegativity of central atom increases, acid strength increases. Thus, Cl is more electronegative than S. 

The binary acids of non-metals exhibit periodic trends in their acid strength, as shown in Figure 8.5. Two factors are responsible for this trend the electronegativity of the atom that is bonded to hydrogen, and the strength of the bond. 

Any substituent that stabihzes a negative charge enhances the dissociation process, i.e. increases the acidity. Electronegative elements can enhance the acid strength through inductive effects. The closer the substituent to the anion, the more profound the effects are. 

Acid strengths of the hydrides of the elements of a period increase from left to right across the period in the same order that electronegativity increases in the periodic table. A highly electronegative element repels an electron of hydrogen atom, and releases it as hydrogen (H" ) ion. Let us consider N, O and F. 

Solid metal sulphates and phosphates also exhibit acid—base properties their acid strength is lower than that of silica—alumina but they are stronger acids than some oxide catalysts [5]. Correlation of activity with electronegativity of cations has been obtained for several reactions [9, 50,51],... 

For binary acids of elements in the same row of the periodic table, changes in the H-A bond strength are smaller, and the polarity of the H-A bond is the most important determinant of acid strength. The strengths of binary acids of the second-row elements, for example, increase as the electronegativity of A increases ... 

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