Which solid displays the greatest solubility in water at 80 °C? O NANO3 NaBr KNO3 KBr

Fluoridation of city water supplies has been practiced in the United States for several decades. It is done by continuously adding sodium fluoride to water as it comes from a reservoir. Assume you live in a medium-sized city of 150,000 people and that 660 L (170 gal) of water is used per person per day. What mass of sodium fluoride (in kilograms) must be added to the water supply each year (365 days) to have the required fluoride concentration of 1 ppm (part per million)that is, 1 kilogram of fluoride per 1 million kilograms of water? (Sodium fluoride is 45.0% fluoride, and water has a density of 1.00 g/cm3.)

Some lithium chloride, LiCl, is dissolved in 100 mL of water in one beaker, and some Li2SO4 is dissolved in 100 mL of water in another beaker. Both are at 10 C, and both are saturated solutions; some solid remains undissolved in each beaker. Describe what you would observe as the temperature is raised. The following data are available to you from a handbook of chemistry:

For each of the following pairs of solutions, select the solution for which solute solubility is greatest. a. Ammonia gas in water with P = 1 atm and T = 50C Ammonia gas in water with P = 1 atm and T = 90C b. Carbon dioxide gas in water with P = 2 atm and T = 50C Carbon dioxide gas in water with P = 1 atm and T = 50C c. Table salt in water with P = 1 atm and T = 60C Table salt in water with P = 1 atm and T = 50C d. Table sugar in water with P = 2 atm and T = 40C Table sugar in water with P = 1 atm and T = 70C

Refer to Figure 13.10 ( Sec. 13-4b) to answer these questions. (a) Does a saturated solution occur when 65.0 g LiCl is present in 100 g H2O at 40 C? Explain your answer. (b) Consider a solution that contains 95.0 g LiCl in 100 g H2O at 40 C. Is the solution unsaturated, saturated, or supersaturated? Explain your answer. (c) Consider a solution that contains 50. g Li2SO4 in 200. g H2O at 50 C. Is this solution unsaturated, saturated, or supersaturated? Explain your answer. Figure 13.10 Solubility of ionic compounds versus temperature.

Maple syrup sap is 3% sugar (sucrose) and 97% water bymass. Maple syrup is produced by heating the sap toevaporate a certain amount of the water. (a) Describe what happens to the composition and boilingpoint of the solution as evaporation takes place. (b) A rule of thumb among maple syrup producers is thatthe finished syrup should boil about 4 C higher than theoriginal sap being boiled. Explain the chemistry behindthis guideline. (c) If the finished product boils 4 C higher than the originalsap, calculate the concentration of sugar in the finalproduct. Assume that sugar is the only solute and theoperation is done at 1 atm pressure.

The solubility of lead nitrate at 100C is 140.0 g/100 g water. A solution at 100C consists of 57.0 g of lead nitrate in 64.0 g of water. When the solution is cooled 10C to 25.0 g of lead nitrate crystallize out. What is the solubility of lead nitrate in g/100 g water at 10C?

Simple acids such as formic acid, HCOOH, and acetic acid, CH3COOH, are very soluble in water; however, fatty acids such as stearic acid, CH3(CH2)16COOH, and palmitic acid, CH3(CH2)14COOH, are water-insoluble. Based on what you know about the solubility of alcohols, explain the solubility of these organic acids.

What is the mole fraction of H 2 S O 4 in a solution containingthe percentage of sulfuric acid and water shownin Figure 14.25?

Silver ions can be found in some of the city water piped into homes. The average concentration of silver ions in city water is 0.028 ppm. (a) How many milligrams of silver ions would you ingest daily if you drank eight glasses (eight oz/glass) of city water daily? (b) How many liters of city water are required to recover 1.00 g of silver chemically?