Place the following aqueous solutions in order of increasing osmotic pressure.
I. 0.15 M C2H6O2 II. 0.15 M BaCl2 III. 0.15 M NaI
To determine the increasing order of osmotic pressure, we need to consider the number of particles the solute will dissociate into when dissolved in water. The more particles, the higher the osmotic pressure.
I. 0.15 M C2H6O2:
C2H6O2 does not dissociate in water; it remains as molecules. Therefore, it only contributes one particle. The osmotic pressure is relatively low for this solution.
II. 0.15 M BaCl2:
BaCl2 dissociates into one Ba²⁺ ion and two Cl⁻ ions when dissolved in water. Therefore, it contributes three particles in total.
III. 0.15 M NaI:
NaI dissociates into one Na⁺ ion and one I⁻ ion when dissolved in water. Therefore, it contributes two particles in total.
In increasing order of osmotic pressure:
I. 0.15 M C2H6O2
III. 0.15 M NaI
II. 0.15 M BaCl2