Sodium chloride, interaction with water

Passage of thionyl chloride through a flexible metal transfer hose which was contaminated with water or sodium hydroxide solution caused the hose to burst. Interaction with water violently decomposes the chloride to hydrogen chloride (2 mol) and sulfur dioxide (1 mol), the total expansion ratio from liquid to gas being 993 1 at 20° C, so very high pressures may be generated. 

This is a good time to bring in a concept that you probably have not encountered before activity. Activity is the effective concentration of a solute, and activity is always less than molality. You need to become increasingly concerned about the difference between molality and activity when the concentration rises above 0.1 molal, especially if you are dealing with ionic solutes. In the previous example, we assumed that sodium chloride dissolves in water to give completely separated ions that have no interactions with each other. Is this reasonable ... 

Benzoyl chloride interacts with hydrogen peroxide in the presence of sodium hydroxide solution to give rise to benzoyl peroxide with the elimination of two moles of hydrochloric acid. The above reaction, being "exothermic in nature, should be carried out in an ice-bath. The excess of sodium hydroxide present in the reaction mixture converts the unreacted benzoyl chloride into sodium benzoate and also reacts with liberated HCl to give sodium chloride. Thus, both sodium benzoate and NaCl being water-soluble remain in the solution, whereas the sparingly soluble benzoyl peroxide gets separated in the reaction mixture. 

One example of an ionic interaction with water molecules is shown in Figure 6.5. Sodium chloride alone in water can be readily measured in spite of its having no NIR bands of its own because it... 

The ion-dipole force occurs when an ionic compound is mixed with a polar compound it is especially important in aqueous solutions of ionic compounds. For example, when sodium chloride is mixed with water, the sodium and chloride ions interact with water... 

Use the data to calculate the heats of hydration of lithium chloride and sodium chloride. Which of the two cations, lithium or sodium, has stronger ion-dipole interactions with water Why ... 

The important chemical properties of acetyl chloride, CH COCl, were described ia the 1850s (10). Acetyl chloride was prepared by distilling a mixture of anhydrous sodium acetate [127-09-3J, C2H202Na, and phosphorous oxychloride [10025-87-3] POCl, and used it to interact with acetic acid yielding acetic anhydride. Acetyl chloride s violent reaction with water has been used to model Hquid-phase reactions. 

In contrast, solid sodium chloride dissolves readily in water at room temperature and without a large heat effect. This can only mean that the water interacts strongly with the ions—so strongly that aqueous ions are about as stable as are ions in the crystal. In fact, water interacts... 

Liu, W. B. Wood, R. H. Doren, D. J., Hydration free energy and potential of mean force for a model of the sodium chloride ion pair in supercritical water with ab initio solute-solvent interactions, 7. Chem. Phys. 2003,118, 2837-2844... 

These potent diuretic agents interact with almost the entire nephron, including Henle s loop (Fig. 7). Their primary effect is probably the inhibition of the active reabsorption of chloride ions, which then leads to the enhanced excretion of sodium ions and water. Plasma volume is reduced as a result of these effects, whereas in the long-term both cardiac preload and afterload will diminish. The metabolic side-effects of the loop diuretics are globally the same as those of the thiazides, with some incidental differences. Plasma renin activity increases by loop diuretic treatment and it can be well imagined that this effect is noxious in the long-term management of heart failure. The loop diuretics provoke a clearly... 

The solubility of molecules can be explained on the basis of the polarity of molecules. Polar, e.g. water, and nonpolar, e.g. benzene, solvents do not mix. In general, like dissolves like i.e., materials with similar polarity are soluble in each other. A polar solvent, e.g. water, has partial charges that can interact with the partial charges on a polar compound, e.g. sodium chloride (NaCl). As nonpolar compounds have no net charge, polar solvents are not attracted to them. Alkanes are nonpolar molecules, and are insoluble in polar solvent, e.g. water, and soluble in nonpolar solvent, e.g. petroleum ether. The hydrogen bonding and other nonbonding interactions between molecules are described in Chapter 2. 

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