The purpose of this lab is to separate a mixture of two compounds using acid-base extraction. The separation by extraction is based on differing solubilities of compounds in two immiscible liquids. The mixtures available for this lab contained a neutral compound and a carboxylic acid. The neutral compounds are benzophenone (Melting point 48-49 ⁰C), 1, 4-dimethoxybenzene (Melting point 58-59 ⁰C), biphenyl (Melting point 71-72 ⁰C), naphthalene (Melting point 81-82 ⁰C), or phenanthrene (Melting point 99-100 ⁰C). The carboxylic acids are benzoic acid (Melting point 121-122 ⁰C) or salicylic acid (Melting point 157-159 ⁰C). These compounds
1. Dissolve 2 g of unknown compound in 30 ml of ether in Erlenmeyer flask.
2. Clean separation funnel (shown on left) using acetone. Make sure the valve is closed then pour acetone in funnel. Fasten funnel with cap. Hold cap in between fingers to make sure the funnel is closed, then swirl acetone around entire funnel (turning funnel over). Pour out acetone. Then transfer ether to separation funnel making sure the valve is closed.
3. Extract your solution with 15 ml 10% NaOH. Swirl funnel around and upside down. Open valve occasionally to let out gas. Once extraction is complete, you should see clear line between both compounds. Drain off lower aqueous layer into fresh beaker labeled "base extract."