A. Write thr reaction equation that occured when a carboxylic acid was extracted

Question

A. Write thr reaction equation that occured when a carboxylic acid was extracted to an aqeous layer (specify the base)

B. Write the reaction equation that occured when a phenol was extracted to an aqeuous layer (specify the base)

Part 1. Separation by Acid-base Extraction Formulas ArOH phenol You will use approximately 0.300 g of the sample. Record the mass with Arco2H carboxylic acid all three decimal places but it does not have to be exactly 0.300 g. This Na neutral compound is a mixture of three unknown components with equal mass. You will Aro Na phenoxide salt need this mass later for your recovery yield calculations ArCO2 Na' carboxylate salt Note: label the tubes! Tube 1' Tube 1 One more extraction with 0.2 mL sat NaHCO AroH add lower layer to tube 2 add 1mL ether AroH ether sat NaHCO3 (aq) N layer layer AroH mix well Separate let layers ArCO2 layers separate Tube 2 Nat aqueous Dissolve 0.30 g mixture Wash with 0.2 mL ether If solid forms at this point, 2mL tert-butyl it is the carboxylate salt. Add ArCO2 Discard methyl ether a few drops of water and mix ether layer Na (ether") well to dissolve all solid. Proceed to aqueous Recovery layer

Explanation / Answer

Before going to write equations one need to question self....

when phenol and carboxylic acid both are acidic then why one need to use two different bases NaHCO3 and NaOH??? why first carboxylic acid extracted why not phenol???

THINK!!

Because carboxylic acid is strong acid

phenol is a weak acid

NaHCO3  is strong base

and NaOH is a weak base

strong acid (carboxylic acid) can be extracted with both weak and strong base (NaHCO3)

whereas weak acid (phenol) extracted only with a strong base (NaOH)

based on this clarity when a strong base is used first it extracts both carboxylic acid and phenol it won't serve our purpose. so, first weak base is used which can extract only strong acid and followed by strong base

now here are your equations

A. ArCOOH + NaHCO3 ===> ArCOO-Na+ + H2CO3

ArCOO-Na+ SALT soluble in water so enters into aqueous layer

B. ArOH + NaOH ===> ArO-Na+ + H2O

ArO-Na+ SALT soluble in water so enters into aqueous layer

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