The vapour pressure ofa pure liquid 'A' is 0.80 atm. When a non-volatile solute 'B' is dissolved in 'A' its vapour pressure becomes 0.60 atm. The mole fraction of 'B' in the solution is
0.125
0.25
0.50
0.75
Which of the following does not show negative deviation from Raoult's law?
Acetone -Chloroform
Acetone-Benzene
Chloroform- Ether
Chloroform- Benzene
50mL of benzene is mixed with 50mL of chloroform. What is the volume of solution?
Less than 100 mL
More than 100 mL
Equal to 100 mL
None of the above
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