Question

What is the reason behind alkane's insolubility in water?

• A. Dipole-dipole forces in water is lesser than Van der Waal force of alkanes and water
• B. Dipole-dipole forces in water is greater than Van der Waal force of alkanes and water
• C. Van der Waal forces in water is greater than Van der Waal force of alkanes and water
• D. Dipole-dipole forces of water is greater than dipole force of alkanes and water

Answer 1

The correct option is B

Dipole-dipole forces in water is greater than Van der Waal force of alkanes and water

Alkane's insolubility in water has some specific reasons based on Van der Waal forces. For alkane to dissolve in water, Van der Waals forces of attraction between alkane molecules and water molecules would have to be greater than the dipole‐dipole forces that exist between water molecules. Apparently, alkanes doesn't show this characteristics.