Question

Part 1 - ExtracHon of an Acidic Organic Compound 1. Secure a small, clean separatory funnel to a ring stand with a clamp. 2. Label three small flask (25 or 50 mL) with one of the following: "benzoic acid", "ethyl-4- aminobenzoate" and "organic layer". 3. Obtain exactly 10.0 mL of a solution containing benzoic acid and ethyl-4-aminobenzonate in ethyl acetate. 4. Extract the solution containing the two compounds with a 3.0 ml. portion of 10% NaOH. General Extraction Procedure Der a. Pour the solution to be extracted into the separatory funnel (make sure the stopcock is closed!). Wash any residual material into the flask using 0.5 mL of solvent. b. Add 3.0 mL of the extracting solvent or solution to the separatory funnel. C. Cap the flask with a glass stopper. d Holding the stopper tightly in place with one hand, invert the funnel. Then use the other hand to open the stopcock, venting the funnel of pressure. e. Close the stopcock and shake the funnel several times so that the two layers are allowed to mix thoroughly. Stop and open the stopcock occasionally, venting the funnel of pressure. f. Once the layers are sufficiently mixed, return the funnel to the upright position (closed stopcock!), and secure it back into the clamp. g. Allow the layers to separate.

how to get %recovery? here recovered benzoic acid is 0.14 g.

Answer 1

Concentration of benzoic acid solution = 20 g/L

Volume of this benzoic acid solution used = 10mL = 0.010L

Amount of benzoic acid in 10mL(0.010L) solution = 20g/L × 0.010L = 0.2g

Amount of benzoic acid recovered = 0.14g

% recovery =( amount recovered/amount used)×100 = (0.14g/0.20g)×100 = 70% recovery .