Which of the following is a colligative property?
Surface tension
Viscosity
Osmotic pressure
Vapour pressure
Four solutions A, B, C, D has glucose 0.5 M, NaCl 0.1 M, BaCl2 0.5 M and MgCl2 0.1 M, then which of the following will have highest osmotic pressure?
Glucose
BaCl2
MgCl2
NaCl
B.
BaCl2
Molar concentration of glucose = 0.5 M
Molar concentration of NaCl = 0.1 M
Molar concentration of BaCl2 = 0.5 M
Molar concentration of MgCl2 = 0.1 M
However as NaCl, BaCl2 and MgCl2 is an electrolyte. One mole of NaCl give two mole ions, therefore molar concentration of particles in the solution = 0.2 M.
One mole of BaCl2 give three mole ions, therefore molar concentration of particles in the solution = 1.5 M.
and one mole of MgCl2 give three mole ions, therefore molar concentration of particles in solution = 0.3 M.
As, osmotic pressure is directly proportional to the number of particles in the solution, hence, increasing order ofosmotic pressure will be.
Glucose < NaCl < MgCl2 < BaCl2
On dissolving a non-volatile solute in a solvent, the vapour pressure of the solvent is decreased by 10 mm of mercury. The mole fraction of the solute in this solution is 0.2. If the vapour pressure of the solvent is decreased by 20 mm of mercury by dissolving more solute, what is the mole fraction of solvent in this solution now?
0.2
0.4
0.6
0.8
During osmosis, flow of water through a semi-permeable membrane is
from both sides of semi-permeable membrane with equal flow rate
from solution having lower concentration only
from solution having higher concentration only
None of the above
Out of the following fractions of petroleum the one having the lowest boiling point is
kerosene oil
diesel oil
gasoline
heavy oil
Two vessels containing gases A and B are interconnected as shown in the figure. The stopper is opened, the gases are allowed to mix homogeneously. The partial pressures of A and B in the mixture will be, respectively
8 and 5 atm
9.6 and 4 atm
4.8 and 2 atm
6.4 and 4 atm
If 0.1 M solutions of each electrolyte are taken and if all electrolytes are completely dissociated, then whose boiling point will be highest?
Glucose
KCl
BaCl2
K2[Fe(CN)6]
The percentage composition by weight of an aqueous solution of a solute (molar mass 150) which boils at 373.26 K (kb = 0.52) is
7
6
9
15