How is it that the boiling points of the following solutions in water are different?
i) 0.1 M NaCl solution
ii) 0.1 M sugar solution
i) 0.1 M NaCl solution
ii) 0.1 M sugar solution
Solution
Elevation of boiling point is a colligative property — it depends on the number of dissolved particles.
NaCl dissociates: each formula unit gives two ions (Na + Cl), so 0.1 M NaCl supplies about 0.2 M particles.
Sugar does not dissociate, so 0.1 M sugar supplies 0.1 M particles.
Hence the NaCl solution boils at the higher temperature, and the two boiling points are different.
NaCl dissociates: each formula unit gives two ions (Na + Cl), so 0.1 M NaCl supplies about 0.2 M particles.
Sugar does not dissociate, so 0.1 M sugar supplies 0.1 M particles.
Hence the NaCl solution boils at the higher temperature, and the two boiling points are different.
CBSE Class 12 Board · 2003 · All India Compartment · Subjective