Sodium chloride dissolving

In contrast to sodium chloride, langbeinite has an extremely slow rate of solution. Upon control of agitation time, essentially all the sodium chloride dissolves but most of the langbeinite remains as a soHd. Langbeinite is separated from the brine, dried, and then screened into granular, standard, and special-standard particle sizes. These fractions are marketed directiy. In one plant, the unsalable fines are used as the source of sulfate reactant for the production of potassium sulfate. 

For example, sodium chloride continues to dissolve in water at 20°C until the concentration is about six moles per liter. The solubility of NaCl in water is 6 M at 20°C. In contrast, only a minute amount of sodium chloride dissolves in ethyl alcohol at 20°C. This solubility is 0.009 M. Even in a single liquid, solubilities differ over wide limits. The solids calcium chloride, CaCl2, and silver nitrate, AgNOa, have solubilities in water exceeding one mole per liter. The solid called silver chloride, AgCl, has a solubility in water of only 10 5 mole per liter. 

First we can investigate, qualitatively, the extent to which the solids dissolve in the liquids. By adding a small piece of each solid to a milliliter of liquid, we easily discover that sugar dissolves both in water and ethyl alcohol, sodium chloride dissolves readily in water but not in ethyl alcohol, and iodine does not dissolve much... 

Water is a very poor conductor of electricity. Yet when sodium chloride dissolves in water, the solution conducts readily. The dissolved sodium chloride must be responsible. How does the dissolved salt permit charge to move through the liquid One possibility is that when salt dissolves in water, particles with electric charge are produced. The movement of these charged particles through the solution accounts for the current. Salt has the formula, NaCl—for every sodium atom there is one chlorine atom. Chemists have... 

With these symbols, we can write the equation for the reaction that occurs when sodium chloride dissolves in water... 

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... 

In Chapter 6 we saw that the chemistry of sodium can be understood in terms of the special stability of the inert gas electron population of neon. An electron can be pulled away from a sodium atom relatively easily to form a sodium ion, Na+. Chlorine, on the other hand, readily accepts an electron to form chloride ion, Cl-, achieving the inert gas population of argon. When sodium and chlorine react, the product, sodium chloride, is an ionic solid, made up of Na+ ions and Cl- ions packed in a regular lattice. Sodium chloride dissolves in water to give Na+(aq) and C (aq) ions. Sodium chloride is an electrolyte it forms a conducting solution in water. 

Are the water molecules oriented in the same way or differently around the positive and negative ions when sodium chloride dissolves Explain your conclusion. 

Sodium chloride dissolves in water Ion-dipole forces of attraction between water molecules and ions are sufficient to overcome the forces between oppositely charged ions in the solid lattice. 

In contrast to sugar, solid sodium chloride dissolves in water to give a liquid that conducts electricity. Figure 3-19 shows that a solution of NaCl is a good conductor. When an ionic compound dissolves in water, its component cations and anions are free to move about in the solution. Mixing leads to a uniform distribution of Na and Cl ions through the entire solution, with each ion surrounded by a sheath of water molecules as shown in Figure 3-20. 

Sodium chloride dissolves more than 25 times better in water than in methanol. Explain this difference, referring to the structure and properties of water, methanol, and sodium chloride. 

A solution consists of a solute dissolved in a solvent- The solute is recoverable from the solution, e.g. sodium chloride dissolved in water is... 

Sodium Chloride. Dissolve about 2 g of sodium chloride in 3 ml of water with heating. Pour the transparent hot solution into a dry test tube. What do you observe when the solution cools ... 

Calcium chloride dissolves to produce three ions, whereas sodium chloride dissolves to produce only two. The greater number of ions generated by calcium chloride is more effective at decreasing the number of water molecules entering the solid phase. 

Tegge12 and Lebedev and coworkers14 have extensively studied the relation between temperature and the stability of 2 D-glucose N aCl H20 in aqueous systems. The fact that this adduct crystallises better than pure D-glucose from aqueous solution is important industrially. o-Glucose may be recovered from its adduct in 77.1% yield by agitating the adduct with water at 5° for 1 hour.14 The sodium chloride dissolves, and the D-glucose remains as a crystalline solid. 

For this study, the composition of the electrolyte was limited to sodium chloride dissolved in de-ionised water in such a way that concentrations of 1 x 10 1, lxlO-2, lxlCT3 and 1 xl0 4molI 1 were obtained.These solutions were... 

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 ... 

Example For example, when 29.25 grams of sodium chloride dissolves in enough water to make one liter of solution. 

Sodium chloride dissolves in water, a very polar solvent. Although the interactions between the water molecules and the sodium and chloride ions are not as strong as the interactions between the ions themselves, they are potent enough to make the process only somewhat endothermic. Entropy then makes the overall process favorable. Sodium chloride does not dissolve in a nonpolar solvent such as pentane (CH3CH2CH2CH2CH3) because the interactions between the pentane molecules and the ions are too weak in comparison to the forces between the ions, making the overall process too endothermic for entropy to overcome. 

Ionization of an alkyl halide requires formation and separation of positive and negative charges, similar to what happens when sodium chloride dissolves in water. Therefore, SN1 reactions require highly polar solvents that strongly solvate ions. One measure of a solvent s ability to solvate ions is its dielectric constant (e), a measure of the solvent s polarity. Table 6-6 lists the dielectric constants of some common solvents and the relative ionization rates for fm-butyl chloride in these solvents. Note that ionization occurs much faster in highly polar solvents such as water and alcohols. Although most alkyl halides are not soluble in water, they often dissolve in highly polar mixtures of acetone and alcohols with water. 

Suppose that a hospital patient requires an intravenous drip to replace lost body fluids. The intravenous fluid may be a saline solution that contains 0.9 g of sodium chloride dissolved in 100 mL of solution, or 0.9% (m/v). Notice that the number of grams of solute per 100 mL of solution is numerically equal to the mass/volume percent. Explore this idea further in the following problems. 

Use the graph on the next page to answer questions 24 and 25. At 80°C, what mass of sodium chloride dissolves in 1.0 L of water ... 

When a molecule splits apart, such as when salt, sodium chloride, dissolves in water to form the separate ions of Na+ and CP. This is also called ionization. 

Sodium Chloride Dissolve about 5 g of sample, accurately weighed, in about 50 mL of water. Neutralize the solution with 1 20 nitric acid, using litmus paper as the indicator add 2 mL of potassium chromate TS and titrate with 0.1 A silver nitrate. Each milliliter of 0.1 A silver nitrate is equivalent to 5.844 mg of sodium chloride (NaCl). 

Sodium Chloride Dissolve about 10 g of sample, accurately weighed, in 50 mL of water in a 250-mL beaker. Add sufficient nitric acid to make the solution slightly acid, then add 1 mL of ferric ammonium sulfate TS and 1.00 mL of 0.05 A ammonium thiocyanate, and titrate with 0.05 A silver nitrate, stirring constantly, until the red color completely disappears. Finally, back titrate with 0.05 A ammonium thiocyanate until a faint red color appears. Subtract the total volume of 0.05 A ammonium thiocyanate added from the volume of 0.05 A silver nitrate required. Each milliliter of 0.05 A silver nitrate is equivalent to 2.922 mg of sodium chloride (NaCl). Calculate the percentage of sodium chloride in the sample taken. Water Calculate the percentage of water by subtracting from 100 the sum of the percentages of Sodium Bicarbonate, Sodium Carbonate, and Sodium Chloride found in the sample. 

When sodium chloride dissolves in water, the H2O molecules orient their dipoles around the Na and Cl ions so that their oppositely charged ends are adjacent to each ion (Figure 15.1). Each sodium or chloride ion in solution is sur-ronnded by many water molecules, lessening the attractions between the ions. Silver chloride, AgCl, does not dissolve in water. Evidently, the ion-dipole attractions are not sufficient to overcome the ion-ion attractions of this solid lattice. The nonpolar solvent benzene, CgHg, cannot dissolve either of these ionic compounds. 

We can also use vapor pressure measurements to characterize solutions. For example, 1 mole of sodium chloride dissolved in water lowers the vapor pressure about twice as much as expected because the ions separate when it dissolves. Thus vapor pressure measurements can give valuable information about the nature of the solute after it dissolves. We will discuss this in more detail in Section 17.7. 

Take, for example, a system whose independent components are water and sodium chloride and which is divided into three phases solid chloride of sodium, an. aqueous solution, and water vapor it may be supposed that sodium chloride dissolves without con densation of water vapor, that water vapor condenses without dissolving sodium chloride, that when a mass of sodium chloride is dissolved and a mass of water vapor condensed, the ratio of these two masses may have any value whatever it may similarly be imagined that the S3nstem undergoes any modifications the opposite of the preceding. 

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