An impure sample contains 0.74 g of impurities and 4.55 g of benzoic acid.  The sample is dissolved in 100 mL of water and heated.  The solution is then cooled. How many grams of the impurity will crystallize when the solution has cooled? Include the unit and two decimal places in your answer. The solubilities of the impurity and benzoic acid in cold and hot water are found as an "item" in the "Recrystallization" folder. Solubility Data for Report Questions  11 Compound Cold Water solubility Hot Water Solubility Benzoic acid 0.42 g per 100 mL of water 5.79 g per 100 mL of water Impurity 0.61 g per 100 mL of water 4.62 g per 100 mL of water

A solution is prepared by adding 425g of AgNO3 to 0.150L of water at 40.0∘C. The solubility of AgNO3 at 40.0∘C is 311g100.mL. How many grams of AgNO3 are expected to precipitate if the temperature is dropped to 0.00∘C where the solubility of AgNO3 is only 122g100.mL? Give the answer with three significant figures.

Why is potassium hydrogen phthalate (KHP) used to standardize the NaOH solution instead of measuring out a known mass of solid NaOH to be dissolved in water? KHP is an acid and will neutralize some of the NaOH to use later. O There is no reason, NaOH solutions can be used without standardization. O Solid NaOH is hygroscopic and will absorb water, making it virtually impossible to determine a true initial mass and therefore changing the concentration of the solution. Solid NaOH evaporates therefore its concentration can never be known.

An aqueous solution of beryllium chloride BECl2 is made by dissolving 1.25g of BECl2 in sufficient water in a 200 ml volumetric flsk and then adding enough water to fill the flask to the mark exactly. What is the weight/volume percentage beryllium chloride in the sollution?

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When answering this problem, report the answer with the appropriate number of significant figures. When entering units, use proper abbreviated units with proper capitalization. A solution is prepared by combining 4.82 grams of an unknown non-electrolyte with 288.0 grams of chloroform. The freezing point of the mixture is --64.96 °C, while the freezing point of pure chloroform is -63.50°C. The kf of pure chloroform is 4.68 °C/molal. Based on this information, determine the moles of solute present in this solution. Your Answer: Answer units

Part 1. One gram of caffeine dissolves in 55 ml of water; 7 ml of dichloromethane (DCM); 530 ml of diethyl ether; and 100 ml of benzene. Covert the solubility of caffeine in these four solvents into units of mg/ml. a) Solubility of caffeine in mg/ml in water: b) Solubility of caffeine in mg/ml in DCM: c) Solubility of caffeine in mg/ml in Diethyl Ether: d) Solubility of caffeine in mg/ml in Benzene: Which is the optimal solvent to extract caffeine from an aqueous solution? Why? Part 1 Continued: Use intermolecular force (IMF), provide a brief explanation on the solubility of caffeine in water, diethyl ether, observed above. (Hint: draw the skeletal structures for caffeine, DCM and diethyl ether)

Give explanation also.

Given: Mass of lauric acid (g): 8.000g Mass of benzoic acid (g): 1.027g Freezing temperature of pure lactic acid(°C): 43.3°C Freezing point of the benzoic acid-lauric acid mixture(°C): 39.8°C m of lauric acid: 1.8m Mols of benzoic acid solute: .0072mol   Question: Determine the accepted molecular weight of benzoic acid from its formula, C6H5CO2H.

A pharmacist mixes togehter 20 g of crystals of compound A and 10g of crystals of compound B. The mixture is then dissolved in 120mL of water to make cough syrup.