Calcium chloride solutions, percent

The leaves of a rhubarb plant contain a relatively high concentration of oxalate ions, C2042-. Oxalate ions are poisonous, causing respiratory failure. To determine the percent of oxalate ions, a student measured the mass of some leaves. Then the student ground up the leaves and added excess calcium chloride solution to precipitate calcium oxalate. The student tested 238.6 g of leaves. The dried mass of calcium oxalate was 0.556 g. What was the mass percent of oxalate ions in the leaves ... 

The RH in most indoor environments is usually not above 70 percent and, thus, the CRH of most common metals is seldom exceeded. The time-of-wetness will be quite small. The corrosion rate is likely to be comparable to the outdoor rate (at similar contaminant levels) when the surfaces are dry. Such rates are insignificant compared to the wet rates for most metals (18). In many cases, the anions associated with deposited substances may play the dominant role in surface processes (24). The concentrations of sulfate, nitrate, and chloride, which accumulate on these surfaces, are likely to increase continuously. After 10 years exposure, total anion concentrations of five to ten /ng/cm can be expected in urban environments. These anions, especially chloride, are well known to dramatically affect the corrosion rates of many metals in aqueous solutions. This acceleration is often a result of solubilization of the surface metal oxide through complexation of the metal by the anions. Chloride, in particular, can dramatically lower the RH above which a moisture film is present on the surface, since chloride salts often have low CRHs (e.g., zinc chloride - < 10 percent calcium chloride - 30 percent and aluminum chloride - 40 percent). The combination of the low CRHs of chloride salts and the well documented ability of dissolved chloride to break down metal oxide passivation set chloride apart from the other common anions in ability to corrode indoor metal surfaces. Some nitrate salts also have moderately low CRHs (e.g., zinc nitrate -38 percent calcium nitrate - 49 percent aluminum nitrate - 60 percent). 

FOLLOW-UP PROBLEM 3.11 Marble (calcium carbonate) reacts with hydrochloric acid solution to form calcium chloride solution, water, and carbon dioxide. What is the percent yield of carbon dioxide if 3.65 g of the gas is collected when 10.0 g of marble reacts ... 

WEIGHT PERCENT CALCIUM CHLORIDE calcium chloride solutions, centipoises (Dow, 2001, courtesy of the... 

A study on the solubiUty of calcium chloride hydrates (3) has generated polymonials relating the weight percent of anhydrous salt in a saturated solution to temperature (°C). For 9.33 < f " C < 28.16... 

Procedure To a dry Erlenmeyer flask of appropriate size, add one half of the reaction solvent. All reactants, including the dry mass of the hydroperoxide, should not constitute more than 23 weight percent of the reaction mixture or an insoluble product may be produced. Add dry lignin and dry calcium chloride to the reaction vessel and cap with a septum or rubber stopper. In a separate vessel, dissolve 2-propenamide in about one quarter of the DMSO solvent and, in a third vessel, dissolve the sulfonated monomer in the final one quarter of the solvent. Saturate both monomer solutions with by bubbling with the gas for 10 minutes. Saturate the lignin solution with for 10 minutes. Add the hydroperoxide to... 

Viscosity of copolymer solutions decreases by, at most, 3 percent when electrolyte concentration changes from 0 to 0.342 M sodium chloride or 2.45 x 10 M calcium chloride. Viscosity of hydrolyzed polymer solutions decreases exponentially with increasing electrolyte concentration in water. 

Calcium chloride, CaCl2, can be used instead of road salt to melt the ice on roads during the winter. To determine how much calcium chloride had been used on a nearby road, a student took a sample of slush to analyze. The sample had a mass of 23.47 g. When the solution was evaporated, the residue had a mass of 4.58 g. (Assume that no other solutes were present.) What was the mass/mass percent of calcium chloride in the slush How many grams of calcium chloride were present in 100 g of solution ... 

You need to calculate the mass/mass percent of calcium chloride in the solution (slush). Then you need to use your answer to find the mass of calcium chloride in 100 g of solution. 

The mass of calcium chloride in 100 g of solution will be numerically equal to the mass/mass percent. 

Calcium chloride is both hygroscopic and deliquescent. Thus, solid material will absorb moisture from the air or snow and ice until it dissolves, and the solution will continue to absorb moisture until an equilibrium is reached between the vapor pressure of the solution and that of the air. At 95 percent relative humidity, one pound of anhydrous calcium chloride will absorb 17.3 lb of water. The ability of calcium chloride to absorb moisture makes it useful in many construction, commercial, and industrial applications. Table 26.13 gives the market distribution of calcium chloride.47 U.S. demand for calcium chloride in 2000 was 1.3 million tons. 

Over 700 tons of mustard agent were destroyed by hydrolysis in Canada (Sutherland, 1997). The destruction was carried out at the Defence Research Establishment Suffield (DRES) in 1975-1976. Alkaline hydrolysis was employed and the products were incinerated. From 1989 to 1991, nerve agents (G and V classes) were removed from weapons using drill-and-drain methods and neutralized using 20 percent potassium hydroxide in methanol. The neutralization products were then incinerated. Lewisite was neutralized with an alkaline peroxide solution containing sodium or calcium chloride. The products included sodium or calcium arsenate, acetylene, and chloride salts. 

Calculate the mass percent of calcium chloride in each of the following solutions. 

Challenge The percent by mass of calcium chloride in a solution is found to be 2.65%. If 50.0 g of calcium chloride is used, what is the mass of the solution ... 

A 450.0-mL sample of a 0.251-M solution of silver nitrate is mixed with 400.0 mL of 0.200 M calcium chloride. What is the concentration of Cl in solution after the reaction is complete 116. The zinc in a 1.343-g sample of a foot powder was precipitated as ZuNH4P04. Strong heating of the precipitate yielded 0.4089 g Zu2P207. Calculate the mass percent of zinc in the sample of foot powder. 

FIG. 8 Crystallization of calcium oxalates in the presence of anionic surfactants (0.3 M sodium chloride solutions supersaturated to COM and COD, pH 6.5, temperature 37°C). Changes in the mass fraction of COD in the precipitate are shown as a function of the surfactant concentration expressed in multiples of the respective critical micelle concentrations (erne s). The mass percent of COD (vertical axis) was calculated from thermogravi-metric data assuming a formula C2O4 2H2O for COD. (After Ref. 62.)... 

Calcium-Magnesium Chloride Solutions Cone. 212-220 100-104 s G — — plus free 0.63 percent HQ in condensate. Alloy C = 6.7 mpy... 

These affinity relationships are reversed in concentrated solutions. This is what makes regeneration of exhausted resins possible. An exhausted cation resin used for softening is predominantly in the calcium and magnesium form, both divalent ions. The resin is restored to its regenerated condition, the sodium form, by the introduction of 10 percent sodium chloride. This sodium chloride solution is concentrated enough (10,000 ppm) to reverse the selectivity. The driving force of the monovalent sodium ion then converts the resin back to the sodium form. 

Percent by Mass proportion of the mass of each element in a compound expressed as a percent or proportion of solute mass as total mass of solution Perfect Gas see Ideal Gas Period a horizontal row in the periodic table Permanent Hardness condition of water when magnesium and calcium are combined with chlorides and sulfates rather than carbonates, cannot be removed by heating Petrochemical chemicals derived from oil or natural gas... 

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