Liquid-Liquid Extraction HW2. Naphthalene is unreactive with NaOH leaving only t

Question

Liquid-Liquid Extraction HW2. Naphthalene is unreactive with NaOH leaving only the phenol to react. plans to separate naphthalene from phenol (shown below) using I M NaOH Phenol A) Fill in the missing pKa values. B) Circle the correct equilibrium arrows (a, b or c) given what you know about weak and strong acids in equilibrium. OH Na NaOH H,O pKa C) Given your data in A and B, is the base chosen strong enough to deprotonate phenol? Explain. D) Outline a liquid-liquid extraction protocol to separate phenol from naphthalene if a 50/50 mixture of the two compounds were both dissolved in diethylether HW 3.List at least two concepts from the lecture that are foundational to understanding the liquid-liquid extraction lab? Copyright © 2016 Rochester Institute of Technology. All Rights Reserved Page 113

Explanation / Answer

A.pka of phenol is 10 and pka of water is 14(at 25degree Celsius)

B.the correct equilibrium arrow is option (a) forward reaction is more favorable as it forms a phenoxide ion which is more stable due to resonance stabilization than phenol

C. Phenol is a weak acid and NaOH is a strong base hence its strong enough to deprotonate phenol there by forming a stable phenoxide ion than phenol.

D. The mixture of naphthalene and phenol can be separated by liquid liquid extraction by adding diethyl ether in which both gets solublised. Now add aqueous sodium hydroxide solution to the mixture which reacts with the phenol to form sodium phenate which enters the water layer separated by ether layer. Now seperate both the layers from separating funnel. To the water layer adding HCl the sodium phenate is converted to phenol back(reacts with the NaOH and neutralises). evaporate the ether layer to get back naphthalene.

Related Questions

Navigate

• Browse (All)
• Browse L
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.