Among the following, the INCORRECT statement about colloids is :
- (A)The range of diameters of colloidal particles is between 1 and 1000 nm
- (B)The osmotic pressure of a colloidal solution is of higher order than the true solution at the same concentration✓ Correct
- (C)They can scatter light
- (D)They are larger than small molecules and have high molar mass
Answer: (B)
Solution
Colloidal particles are – nm across, they scatter light through the Tyndall effect, and they are large with high molar mass, so those statements all hold. The false one concerns osmotic pressure: because the particles are large, a given mass contains far fewer of them than a true solution would, so a colloid's osmotic pressure is actually lower, not higher. That claim of higher osmotic pressure is the incorrect statement.
JEE Main · 2019 · 12 Apr 2019 · Shift 2 · Single correct option