Acids substances Oxyacids

Silicic acid. Any oxyacid of silicon, such as orthosilicic acid, H4SK>4, meta-silicic acid, H2Si03. These substances are hypothetical compounds inferred from their metallic or organic derivatives. 

From the preceding, it should be remembered that tyrosin, phenylalanin, tryptophane, and the amino-acids substances that remain unchanged in he hydrol3 es realized by the digestive enzymes, are, on the contrary, the substances which are the most easily transformed in putrefactions, since they give rise to numerous derivatives, oxyacids, indol, and phenols. One of the characteristics of the action o the amidases secreted by the putrefactive bacteria appears to be the fact that they address themselves preferably to the aromatic substances which have come from proteolysis. 

This disintegration of the albuminoid substance, which converts almost the whole of the organic nitrogen into ammonia, results from the combined action of numerous micro-organisms, of different species and nature. The products elaborated by one class of bacteria often serve as the point of attack for another. Thus the volatile acids and oxyacids furni.shed in the course of ammoniacal fermentation constitute a nutritive rruitcrial for the ferments of cellulose, bacteria abundantly represented in the soil Calcium acetate, as well as its homologues, react under these conditions in the following manner ... 

The chemist is much concerned with the relationship between the structure and reactivity of substances. A knowledge of such a relationship enables the chemist to make new compounds which have certain desired properties. The Brdnsted acid-base reaction is a common and relatively simple reaction we therefore use it to discuss the relationship of structure and reactivity. We here restrict our discussion to the oxyacids and oxyanions. We will first present the facts about reactivity, and then we will present a broad concept to rationalize the relative reactivities. The acidity of oxyacids follows periodic patterns and is also influenced by the oxidation number of the central atom. 

The most common oxyacid of sulfur is H2S04, sulfuric acid. In dilute aqueous solutions this substance is almost completely dissociated into ions according to the equation... 

Prepare a solution of iodic acid (see p. 109) and pour it into two test tubes. Pour a potassium iodide solution into one tube. What substance evolves Pour an iron(II) sulphate solution into the other tube. What do you observe Write the equations of the reactions. What properties of iodic acid do the above experiments indicate Write the formulas of the iodine oxyacids. What oxygen compounds of iodine are known How are they prepared ... 

According to the Bronsted—Lowry deHnition (Section 2.7), an cicid is any substance that donates H. Altiioi h we usually think of oxyacids (H2SOJ, HNOj) or halogen acid.s (HC1, HBr) in this context, any compound containing a hydrc en atom can be an add under the ri t circumstances. By measuring dissociation constants of dilFerent adds and expressii the results as pX, values, an acidity order can be established. Recall from Section 2.8 that a low pK corresponds to a strong add, and a high pK corresponds to a weak acid. 

Oxyacids (often called oxoacids) are molecular substances that have the general formula H XbOc. In other words, they contain hydrogen, oxygen, and one other element represented by X the a, b, and c represent subscripts. The most common oxyacids in the chemical laboratory are nitric acid, HNO3, and sulfuric acid, H2SO4. 

Identify the following substances as composed of polar molecules water, H2O ammonia, NH3 oxyacids (such as nitric acid, HNO3) hydrogen halides (HF, HCl, HBr, and HI) methanol, CH3OH and ethanol, C2H5OH. 

Strong acid Weak acid Diprotic acid Oxyacids Organic acids Carboxyl group Amphoteric substance Ionization of water Ion-product constant... 

Arrhenius concept Bronsted-Lowry model hydronium ion conjugate base conjugate acid conjugate acid-base pair acid dissociation constant Section 14.2 strong acid weak acid diprotic acid oxyacids organic acids carboxyl group monoprotic acids amphoteric substance autoionization... 

Analyze We are asked to arrange two sets of compounds in order from weakest acid to strongest acid. In (a), the substances are binary compounds containing H, and in (b) the substances are oxyacids. 

According to the Bronsted-Lowry definition (Section 2.7), an acid is a substance that donates H" ". Although we usually think of oxyacids (H2SO4, HNO3) or halogen acids (HCl, HBr) in this context, any compound containing... 

---