Stereochemistry of organic compounds by d nasipuri pdf free download

STEREOCHEMISTRY OF ORGANIC COMPOUNDS BY D NASIPURI PDF FREE DOWNLOAD SERIES

= insoluble litmus is red at ph below 4.5 and blue above 8.3.Д¤ TABLE.1 Organic Compounds Comprising the Solubility Classes S 2 Salts of organic acids (RC0 2 Na, RS0 3 Na) amine hydrochlorides (RNH 3 Cl) amino acids S A S B S1 A1 A2 B MN N I 'Acyl polyfunctional compounds with hydrophilic functional groups: carbohydrates (sugars), polyhydroxy compounds, polybasic acids, etc. Figure (1) Classification of organic compounds by solubility: determination in water, acids, bases, and ethers (see Table 5.1 for compounds comprising each class), sol. Once the compound is identified as an acid and its solubility class determined, then no more solubility tests are needed. Strong and weak acids (solubility classes A 1 and A 2 see Table.(1) and Figure (1) are differentiated by their solubility or lack of solubility in 5% sodium bicarbonate solution. Acidic compounds are identified by their solubility in 5% sodium hydroxide solution. However, if the compound is not soluble in water, then it is tested for solubility in 5% sodium hydroxide solution. No more solubility tests are needed at this point if the compound is soluble in water. Solubility in ether indicates that the compound is in solubility classes S A, S B, or S 1 The aqueous solutions of the ether soluble compounds are thenДЈ tested with ph paper to narrow down the choices. If the compound is insoluble in ether, then it is in solubility class S 2. If the compound is soluble in water, then it is tested for solubility in ether.

In considering solubility in water, a substance is arbitrarily said to be 'soluble' if it dissolves to the extent of 3.3 g/100 ml of solvent. Compounds are first tested for solubility in water.

STEREOCHEMISTRY OF ORGANIC COMPOUNDS BY D NASIPURI PDF FREE DOWNLOAD SERIES

For example, in many homologous series of monofunctional compounds, the members with fewer than about five carbon atoms are water soluble, whereas the higher homologs are insoluble. Finally, certain deductions about molecular size and composition may sometimes be made.

In this case, then, the solubility in 5% sodium hydroxide solution of a water insoluble unknown is a strong indication of an acidic functional group. For example, benzoic acid is insoluble in a polar solvent, water, but is converted by 5% sodium hydroxide solution to a salt, sodium benzoate, which is readily water soluble. Second, solubility in certain solvents often leads to more specific information about the functional group. For instance, because hydrocarbons are insoluble in water, the mere fact that an unknown is partially soluble in water indicates that a polar functional group is present.

First, the presence of a functional group is often indicated. Although the two solubility sections below are interrelated, the first section deals primarily with the identification of functional groups and the second with the determination of solvents to be used in recrystallizations, spectral analyses, and chemical reactions.Дў SOLUBILITY IN WATER, AQUEOUS ACIDS AND BASES, AND ETHER Three kinds of information can often be obtained about an unknown substance by a study of its solubility in water, 5% sodium hydroxide solution, 5% sodium bicarbonate solution, 5% hydrochloric acid solution, and cold concentrated sulfuric acid. The solubility of organic compounds can be divided into two major categories: solubility in which a chemical reaction is the driving force, for example, the following acid-base reaction, and solubility in which simple miscibility is the only mechanism involved, such as dissolving ethyl ether in carbon tetrachloride. Solubility involves the formation of one layer, if the compounds are miscible, or two layers, if the compounds are immiscible. In some cases, a chemical reaction is occur by a change in color or heat or by the formation of a precipitate. Before proceeding, the difference between solubility and a chemical reaction must be explain. 1 Classification of organic compounds By solubility In this experiment we begin the process of determining the structural composition of organic compounds based upon interpretation of simple solubility tests can be extremely useful in organic structure determination.

Stereochemistry of organic compounds by d nasipuri pdf free download