Advertisements
Advertisements
Question
How will you determine molar mass of solute from osmotic pressure?
Advertisements
Solution
For very dilute solution, osmotic pressure is given by
πV = n2RT
where,
π = Osmotic pressure in atm.
V = Volume of a solution in dm3
n2 = Moles of non-volatile solute
R = Gas constant = 0.082L dm3 atm K−1mol−1
T = temperature in Kelvin
∴ `pi = (n_2RT)/V`
`pi = (W_2RT)/(M_2V) ...[because n_2 = W_2/M_2]`
∴ `M_2 = (W_2 R T)/(pi V)`
APPEARS IN
RELATED QUESTIONS
Determine the osmotic pressure of a solution prepared by dissolving 2.5 × 10−2 g of K2SO4 in 2L of water at 25°C, assuming that it is completely dissociated.
(R = 0.0821 L atm K−1 mol−1, Molar mass of K2SO4 = 174 g mol−1)
Which of the following is not a colligative property?
What happens when the external pressure applied becomes more than the osmotic pressure of solution?
Calculate the osmotic pressure in pascals exerted by a solution prepared by dissolving 1.0 g of polymer of molar mass 185,000 in 450 mL of water at 37°C.
At 300 K, 36 g of glucose present in a litre of its solution has an osmotic pressure of 4.98 bar. If the osmotic pressure of the solution is 1.52 bars at the same temperature, what would be its concentration?
Define osmotic pressure.
Which of the following 0.1 M aqueous solutions will exert the highest osmotic pressure?
Define Semipermeable membrane
Calculate the mass of NaCl (molar mass = 58.5 g mol−1) to be dissolved in 37.2 g of water to lower the freezing point by 2°C, assuming that NaCl undergoes complete dissociation. (Kf for water = 1.86 K kg mol−1)
Calculate the mass of a compound (molar mass = 256 g mol−1) to be dissolved in 75 g of benzene to lower its freezing point by 0.48 K (Kf = 5.12 K kg mol−1).
Define the following term:
isotonic solution
Choose the most correct option.
In calculating osmotic pressure the concentration of solute is expressed in _______.
Choose the most correct option.
The osmotic pressure of blood is 7.65 atm at 310 K. An aqueous solution of glucose isotonic with blood has the percentage (by volume)________.
Answer the following in one or two sentences.
What is osmotic pressure?
Answer the following.
The osmotic pressure of CaCl2 and urea solutions of the same concentration at the same temperature are respectively 0.605 atm and 0.245 atm, calculate van’t Hoff factor for CaCl2.
Answer the following.
Explain reverse osmosis.
An aqueous solution of a certain organic compound has a density of 1.063 g mL-1 , osmotic pressure of 12.16 atm at 25 °C and a freezing point of 1.03 °C. What is the molar mass of the compound?
Which of the following statements is applicable for 0.1 M urea solution and 0.1 M sucrose solution?
What are hypertonic solutions?
Explain the phenomenon of osmosis.
Define Osmosis.
Two solutions have different osmotic pressures. The solution of higher osmotic pressure is called ____________.
At constant temperature the osmotic pressure of a solution is ____________.
20 g of a substance were dissolved in 500 mL of water and the osmotic pressure of the solution was found to be 600 mm of mercury at 15°C. The molecular weight of the substance is:
A solution containing 10 g per dm3 of urea (molar mass 60 g mol−1) is isotonic with 5% solution of non-volatile solute, MB of solute is:
At a given temperature, osmotic pressure of a concentrated solution of a substance ______.
Which of the following statements is false?
Isotonic solutions must have the same:
(i) solute
(ii) density
(iii) elevation in boiling point
(iv) depression in freezing point
In isotonic solutions:
(i) Solute and solvent both are same.
(ii) Osmotic pressure is same.
(iii) Solute and solvent may or may not be same.
(iv) Solute is always same solvent may be different.
Match the items given in Column I and Column II.
| Column I | Column II |
| (i) Saturated solution | (a) Solution having same osmotic pressure at a given temperature as that of given solution. |
| (ii) Binary solution | (b) A solution whose osmotic pressure is less than that of another. |
| (iii) Isotonic solution | (c) Solution with two components. |
| (iv) Hypotonic solution | (d) A solution which contains maximum amount of solute that can be dissolved in a given amount of solvent at a given temperature. |
| (v) Solid solution | (e) A solution whose osmotic pressure is more than that of another. |
| (vi) Hypertonic solution | (f) A solution in solid phase. |
Discuss biological and industrial importance of osmosis.
Osmotic pressure of a solution increases if
Which of the following colligative property can provide molar mass of proteins (or polymers or colloids) with greatest precision?
Isotonic solutions have same
Which one of the following is a colligative property?
Osmotic pressure of a solution containing 2 g dissolved protein per 300 cm3 of solution is 20 mm of Hg at 27°C. The molecular mass of protein is ______.
Determine the osmotic pressure of a solution prepared by dissolving 2.32 × 10−2 g of K2SO4 in 2L of solution at 25°C assuming that K2SO4 is completely dissociated.
(R = 0.082 L atm K−1 mol, Molar mass K2SO4 = 174 g mol−1)
Isotonic solutions are the solutions having the same ______.
Arrange the following solutions in the order of increasing osmotic pressure (π) assuming complete ionization.
- 0.5M Li2 SO4
- 0.5M KCl
- 0.5M Al2 (SO4)3
- 0.1 M BaCl2
Define reverse osmosis.
Write the condition of reverse osmosis.
