Question

Addition of solid non-volatile impurities in a liquid

• A. decreases its boiling point
• B. increases its boiling point
• C. does not affect its boiling point
• D. first decreases then increases its boiling point

Answer 1

The correct option is B increases its boiling point

When a solid non-volatile impurity is added to a liquid, some particles of liquid get replaced by the particles of solid at the surface; thereby the fraction of the surface covered by the liquid particles gets reduced. This means that lesser number of particles move into the vapour state and higher energy is required for boiling. Thus, an increase in the boiling point is observed.
Hence, the correct answer is option (b).