Specific heat hydrochloric acid

Some agrochemicals bind strongly to the soil component as bound residues, which cannot be extracted without vigorous extraction procedures. In this case, an acidic (e.g., hydrochloric acid, sulfuric acid) or alkaline solution (e.g., sodium hydroxide, potassium hydroxide) can be used as an extraction solvent, and also heating may be effective in improving the extraction of the residues. Analytical procedures after the extraction are the same as above, but a filtration procedure may be troublesome in some of these situations. However, these procedures are rare exceptions or are needed for specific chemicals that are stable under such harsh extraction conditions. 

The saponification number expresses the amount of base that will react with 1 g of a sample when heated in a specific manner. Since certain elements are sometimes added to asphalt and also consume alkali and acids, the results obtained indicate the effect of these extraneous materials in addition to the saponifiable material present. In the test method (ASTM D94 IP 136), a known weight of the sample is dissolved in methyl ethyl ketone or a mixture of suitable solvents, and the mixture is heated with a known amount of standard alcoholic potassium hydroxide for between 30 and 90 minutes at 80°C (176°F). The excess alkali is titrated with standard hydrochloric acid and the saponification number is calculated. 

Why was it fair to assume that the hydrochloric acid solution has the same density and specific heat capacity as water ... 

When the reaction occurs, the temperature of the hydrochloric acid rises from 14.5"C to 29.7"C. What is the percentage purity of the sample Assume that the specific heat capacity of the hydrochloric acid is 4.184 J/g°C. Also assume that all of the zinc in the impure sample reacts. 

Specific heat.—The sp. ht., (7, of soln. of hydrochloric acid with n mol. of water per mol. of hydrogen chloride have been determined by J. Thomsen,21 J. C. G. de Marignac, and H. Hammerl. The following are compiled from these data ... 

Lae resin is very difficultly soluble in alcohol, though, like copal, it may be completaly teken up by this advent. Like most of the other resins, It has a strong affinity for bases, with which it forms definite compounds. Dilute hydrochloric acid and acetic acid dissolve the rosin freely, but not the strong sulphurto acid. Borax solutions with the aid of heat also take it up. The portion soluble in alcohol has a specific gravity of 1-139, IIhvekdokbeN found it to be a compound of several rosins, namely—... 

The density of CusAs is 6-7 to 7-7 the density calculated from crystallographic data 5 is 8-22. The hardness is 3-0 to 3-3 on Mohs scale. The specific heat is 6 0-0919. On heating, sublimation occurs at 345° to 370° C.7 The arsenide decomposes on strong heating.8 It is completely reduced when heated in hydrogen.9 It is stable towards hydrochloric acid, but is attacked by nitric acid.10... 

Another classic resolution process developed by Ethyl Corp. for (S)-ibuprofen production uses (S)-(-)-a-methylbenzylamine (MAB) as the chiral base for diastereomeric salt formation 49 The difference in solubility between (S)- and (ft)-ibuprofen MAB salts is so substantial that only half an equivalent of MAB is used for each mole of racemic ibuprofen, and no seeding is needed. The process can also be performed in a wide range of solvents, and the unwanted (ft)-ibuprofen can be recycled conveniently by heating the mother liquor in sodium hydroxide or hydrochloric acid. Other designer amines have been developed for resolution of ibuprofen with good stereoselectivities,50 but these chiral amines were prepared specifically for ibuprofen resolution and are thus unlikely to be economical for industrial production. 

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