Strength of oxyacids

In the series of oxyacids of chlorine, the acid strength in aqueous solution is in the order HCIO4 HCIO3 HCIO2 HOCl 

Acid Strongest HCIO4 HCIO3 HCIO2 Weakest HOCl 

For oxyacids with more than one ionizable hydrogen, the pK values increase by about 5 units with each successive proton removal  

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However, the strength of oxyacids does not depend only on the oxidation state of the central atom, but on structural factors as well. For example, the acid HsPOa, in which one hydrogen atom is attached directly to the phosphorus and cannot ionize, is somewhat stronger than H3PO4, in spite of the lower oxidation number of the phosphorus, +3 as compared with - -5 the first ionization constants are 1.6 X ICi" and 7.5 X 10 , respectively. The acid H4P2O7... 

We can summarize these ideas as two simple rules tiiat relate tire acid strength of oxyacids to tiie electronegativity of Y and to tiie number of groups attached to Y. 

Chlorine forms a number of oxyacids. Which of the following is the correct order of increasing acid strength ... 

What products form when disubstituted sodium and ammonium-sodium orthophosphates are roasted What orthophosphates are used as fertilizers Compare the strength of the oxyacids of phosphorus, sulphur, and chlorine, and also of nitrogen and phosphorus. 

More important for inorganic oxyacids is the number of oxygen atoms surrounding the central atom. Thus in the series of chlorine oxyacids. acid strength increases in the order HOCI < HOClO < H0C102 <- HOClOj. The trends in acidity of oxyacids, and even reasonably accurate predictions of their pKu values, can be obtained from 19... 

Low-temperature CO adsorption measurements indicate that the strength of Bronsted acid sites on reduced catalysts are lower than those characteristic of the oxidized catalyst.27 This finding is not unexpected, as it is well known that the acid strength of inorganic oxyacids depends on the oxidation state of the central atom.30... 

The adsorption of anions of weak oxyacids indicates a Lewis acid character of the Ft surface. The tendency of the metal to attract electrons, in particular in the case of Pt(l 11), is reflected in several facts. Thus anions of weak acids tend to dissociate on the surface, indicating that the strength of the adsorbed acids is enhanced by the metal. Furthermore, the anions seem to transfer their charge to a great extent, at least in the case of adsorption at Pt(lll), as demonstrated by the experiment of Orts et al. [154] and indirectly confirmed by the high degrees of coverage reached by adsorbed sulfate ions on this surface. 

How does the oxyacid strength of the halogens vary as the number of oxygens in the formuia increases ... 

The acid strength of the oxyacids of chlorine in aqueous solution rank as HCIO4 > HCIO3 > HCIO2 > HOCl The pKa values of these acids are below. 

The oxidation states of the halogens vary from -1 to +7. Identify compounds of chlorine that have 1, -1-1, -1-3, -1-5, and -1-7 oxidation states. How does the oxyacid strength of the halogens vary as the number of oxygens in the formula increases ... 

How does the acid strength of an oxyacid depend on (a) the electronegativity of the central atom (b) the number of non-protonated oxygen atoms in the molecule ... 

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