Using complete sentences, briefly answer the following: A) Accurately describe the procedural steps for partitioning 2-propanol from 70% rubbing alcohol. B) What is the name and the advantage of this technique? C) Briefly explain how it works? Solution A) Isopropyl alcohol or 2-propanol is miscible in water but is immiscible in salt solutions.It forms distinct layer when salt like sodium chloride is added to its mixture with water (70 % 2-propanol+30% water) and separates from the aqueous layer. B) This technique is called salting out. C) Using this technique,liquids can be separated from their azeotropic mixtures using separating funnel.2-propanol dissolves in water by forming hydrogen bonds (partially miscible in water forming azeotrope).Salt being polar dissolves in polar aqueous medium but not in non-polar organic medium of 2-propanol.Thus, hydrogen bonds between 2-propanol and water is broken,rather salt ions form stronger polar electrostatic bonds with water molecules.The two liquids thus ,separates forming two distinct layers. The liquids forming two distinct layers ,one organic(2-propanol) and one aqueous layer can be seprated by draining out the liquid forming lower layer (less dense liquid 2-propanol). .

1. Using complete sentences, briefly answer the following: A) Accurately describe the procedural
steps for partitioning 2-propanol from 70% rubbing alcohol. B) What is the name and the
advantage of this technique? C) Briefly explain how it works?
Solution
A) Isopropyl alcohol or 2-propanol is miscible in water but is immiscible in salt solutions.It
forms distinct layer when salt like sodium chloride is added to its mixture with water (70 % 2-
propanol+30% water) and separates from the aqueous layer.
B) This technique is called salting out.
C) Using this technique,liquids can be separated from their azeotropic mixtures using separating
funnel.2-propanol dissolves in water by forming hydrogen bonds (partially miscible in water
forming azeotrope).Salt being polar dissolves in polar aqueous medium but not in non-polar
organic medium of 2-propanol.Thus, hydrogen bonds between 2-propanol and water is
broken,rather salt ions form stronger polar electrostatic bonds with water molecules.The two
liquids thus ,separates forming two distinct layers.
The liquids forming two distinct layers ,one organic(2-propanol) and one aqueous layer can be
seprated by draining out the liquid forming lower layer (less dense liquid 2-propanol).