Methanoic acid mixes with water in all proportions and has about the same boiling point as water. Which of the following methods would you adopt to obtain pure water from a mixture of Sand, water and methanoic acid?
Extractive distillation
Filtration followed by distillation
Neutralization with sodium hydroxide followed by distillation
Neutralization with sodium hydroxide followed by filtration
Correct answer is A
Due to the presence of maximum Azeotrope,we use extractive distilination (with extractive distilation agents like sulfone) used for mixtures with low relative volatility,nearing unity.
Azeotrope is a mixture of liquids that has a constant boiling point because the vapour has thesame composition as the mixture.