Solutes and saturation

Ethyl formate. Reflux a mixture of 61 g. (50 ml.) of A.R. formic acid (98/100 per cent.) and 31 g. (39-5 ml.) of absolute ethyl alcohol for 24 hours. Transfer to a Claisen flask with fractionating side arm (or attach a fractionating column to the flask), distil and collect the liquid passing over below 62°. Wash the distillate with saturated sodium bicarbonate solution and saturate with salt before removing the ester layer. Dry with anhydrous sodium or magnesium sulphate, filter, and distil. The ethyl formate passes over at 53-54°. The yield is 36 g. 

The organic fractions are combined and washed successively with N,N-dimethyl-1,3-propane-diamine, dilute hydrochloric acid, saturated sodium bicarbonate solution and saturated sodium chloride solution. The organic fraction is dried over anhydrous magnesium sulfate. The solvent is then evaporated off. Upon trituration of the residue with methanol, a solid crystallizes, 5-(p-toluovl)-1 -methvlpvrrole-2-acetonitrile, which is removed by filtration and purified by recrystallization from benzene. 

Elevation of boiling point by dissolved solids results in differences of 3-10°F between solution and saturated vapor. 

One pet owner recently prescribed the following home remedy to eliminate skunk odor Add 1/4 cup of baking soda and 1 teaspoon of liquid detergent to 1 quart of hydrogen peroxide. Soak a rag with the solution and saturate the affected areas, rubbing it in. 111 What valuable chemistry is working to deodorize your dog ... 

Table 3.1. The major ion composition of dispersed soil solutions and saturation extracts from selected soils in California, U.S. 

The major ion composition of dispersed soil solutions and saturation extracts from selected soils in California, U.S. Concentrations of trace elements in soil solutions of the California soils that received sludge applications. Concentrations of trace elements in soil solutions extracted by saturated paste from two metal salt-spiked Israeli soils incubated at saturated regime. 

In this process, 1.2 g of ll-(3-dimethylaminopropyl)-ll-hydroxy-2-(2-triphenylmethyloxyethyl)-6,ll-dihydrodibenz[b,e]oxepin is dissolved in 50 ml of pyridine. To the solution is dropwise added 0.8 g of phosphorusoxychloride under a nitrogen atmosphere and ice-cooling. After stirring the mixture at room temperature for one hour, the solvent is distilled away under reduced pressure. The residue is extracted with 100 ml of methylene chloride, and washed with saturated aqueous sodium bicarbonate solution and saturated aqueous sodium chloride solution in order. After drying the mixture over anhydrous sodium sulfate, the solvent is distilled away under reduced pressure. The resultant residue is purified by column chromatography on silica gel (eluent hexane ethylacetate triethylamine = 10 10 1) to obtain 0.82 g of the desired product as a colorless oily matter. 

Boron tribromide (1.56 mmol) was slowly added to a solution of the Step 4 product (1.2 mmol) dissolved in 8 ml CH2C12 at -10°C and the mixture stirred 90 minutes. It was quenched with 30 ml methyl alcohol, then warmed to ambient temperature, and stirred an additional 2 hours. The mixture was diluted with CH2C12 and washed with water, 1M HC1, saturated NaHC03 solution, and saturated brine. The solution was dried, then concentrated, and a solid orange residue isolated. The residue was... 

A solution of 40% aqueous benzyltrimethylammonium hydroxide (0.832 mmol) was added to a solution of the Step 6 product (0.64 mmol) dissolved in 5 ml DMF and treated with methyl bromoacetate (1.28 mmol), then stirred 2 hours at ambient temperature. Cesium carbonate (0.32 mmol) was then added as a solid and the mixture stirred an additional hour. The mixture was then diluted with EtOAc and washed with water, 1 M HC1, saturated NaHC03 solution, and saturated brine. It was dried using MgS04, concentrated, purified by chromatography using EtOAc, and the product isolated in 53% as a brown foam, mp = 120—125°C. 

Sodium sulphide (2m). To 16 g solid sodium hydroxide, NaOH, add 20 ml water. Cover the beaker with a watch glass and shake the mixture gently, until complete dissolution. Dilute the mixture with water to 100 ml. Take 50 ml of this solution and saturate with hydrogen sulphide gas. Then add the rest of sodium hydroxide solution to the latter. 

Incompatibilities poorly compatible with citric acid, saccharose solutions, and saturated sodium bicarbonate solutions. Incompatible with ascorbic acid, gelatin, and glucose. Method of manufacture diazotized sulfanilic acid is coupled with Schaeffer s salt (sodium salt of (3-naphthol-6-sulfonic acid). 

Figure 8.3. Two-electrode cell used to measure electrical conductivity of solutions and saturated soil pastes.

Procedure (a) In the preliminary test, mix small amounts of 0.1 M sulfuric acid solution and saturated barium hydroxide solution. Observe and explain the precipitation of white crystal deposit, (b) Place 50 ml of barium hydroxide solution in a beaker, add the indicator solution, switch on the magnetic stirrer, and dip the conductivity tester into the solution. Fill the burette with sulfuric... 

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