Question

An organic acid is dissolved in methylene chloride (d=1.3 g/mL), which is then extracted with aqueous NaOH (d=1.0 g/mL). Will the organic acid be present in the top or the bottom layer. Provide a brief explanation.

Answer 1

Hey there!

Organic acid present in the methylene chloride when treated with aqueous NaOH it will be converted to aqueous soluble sodium carboxylate salt as shown below :

RCOOH (DCM layer) + NaOH ----------------> RCOONa (aqueous layer) + H₂O

the organic layer methylene chloride is immiscible with water, therefore it will present as two-layer, the large denser layer will present at the bottom

Density of dichloromethane = 1.325 g/mL

Density of water = 1 g/mL

Since dichloromethane density is more it will present at the bottom and water density is lesser, therefore, it will present its top, since RCOONa is aqueous soluble it present at the top aqueous layer

*Organic acid will present in the top layer