Advertisements
Advertisements
प्रश्न
For a very dilute solution, the osmotic pressure is given by π = n2RT/V where V is the volume in L containing n2 moles of nonvolatile solute. Establish the equation for molar mass of solute.
Advertisements
उत्तर
For very dilute solutions, the osmotic pressure follows the equation,
`pi = ("n"_2 "RT")/"V"` ....(1)
If the mass of solute in V litres of solution is W2 and its molar mass is
M2, then n2 = `"W"_2/"M"_2`
Substituting the value of n2 in equation (1), we get
`pi = "W"_2/"M"_2 "RT"/"V"`
∴ M2 = `("W"_2"RT")/(pi"V")`
This formula can be used for the calculation of molar mass of a nonionic solute (i.e., nonelectrolyte), by osmotic pressure measurement.
संबंधित प्रश्न
Choose the most correct option.
Pressure cooker reduces cooking time for food because _______.
Answer the following.
Why vapour pressure of a solvent is lowered by dissolving a nonvolatile solute into it?
The following solution/solvent has maximum vapour pressure _______.
Write the expression for relative lowering of vapour pressure.
The vapour pressure of a pure liquid is 0.043 bar at a certain temperature. When a nonvolatile solute is dissolved into it, the vapour pressure of the solution is found to be 0.041 bar. What is the relative lowering of vapour pressure?
Give two points to explain why vapour pressure of solvent is lowered by dissolving nonvolatile solute into it.
Which of the following is NOT a colligative property?
The vapour pressure of pure solvent and solution are 120 mm Hg and 108 mm Hg respectively. The mole fraction of the solvent in the solution is ____________.
In an experiment, 1 g of a non-volatile solute was dissolved in 100 g of acetone (molar mass = 58 g mol−1) at 298 K. The vapour pressure of the solution was found to be 192.5 mm Hg. The molecular weight of the solute is (vapour pressure of acetone = 195 mm Hg) ____________ g mol−1.
Which of the following is CORRECT statement?
The vapour pressure of pure benzene (molar mass 78 g/mol) at a certain temperature is 640 mm Hg. A nonvolatile solute of mass 2.315 g is added to 40 g of benzene. The vapour pressure of the solution is 600 mm Hg. The molar mass of solute is ______.
According to Raoult's law, relative lowering of vapour pressure for a solution containing a nonvolatile solute is equal to ____________.
Which of the following is INCORRECT expression in terms of vapour pressure of pure solvent `("P"_1^0)` and that of solution (P)?
The vapour pressure of water at 20°C is 17 mm Hg. The vapour pressure of solution containing 2.8 g urea in 50 g of water is ____________.
Which of the following changes will cause increase in vapour pressure of 1 molal aqueous KI solution at same temperature?
Relative lowering in vapour pressure depends on _______.
38.4 g of unknown substance (molar mass 384 g mol-1) and 116 g of acetone is used to prepare a solution at 313 K. If vapour pressure of pure acetone (molar mass 58 g mol-1) is 0.842 atmosphere, what is the vapour pressure of solution?
12 g of a nonvolatile solute dissolved in 108 g of water produces the relative lowering of vapour pressure of 0.1. The molecular mass of the solute is ______.
Calculate the mole fraction of solute, if the vapour pressure of pure benzene at a certain temperature is 640 mmHg and the vapour pressure of a solution of a solute in benzene is 600 mmHg.
