Question

2. Based on the percentages of isopropyl alcohol and water in the 40% isopropyl alcohol in water or 60% isopropyl alcohol in water solutions, which is more polar, 40% or 60%? Explain your answer.

Answer 1

Given solvent systems:

40% isopropyl alcohol in water = 40% isopropyl alcohol + 60% water

60% isopropyl alcohol in water = 60% isopropyl alcohol + 40% water

40% isopropyl alcohol in water is more polar than 60% isopropyl alcohol in water.

Explanation:

Water is more polar than isopropyl alcohol because isopropanol contains non-polar C-C,C-H bonds where as the water has polar O-H bonds.

So,

more is the water in the solvent system, more is the polar nature.

less is the water in the solvent system, less is the polar nature.

Therefore,

40/60 isopropyl alcohol/H2O is more polar than 60/40 isopropyl alcohol/H2O.

i.e.40% isopropyl alcohol in water is more polar than 60% isopropyl alcohol in water.