List of top Chemistry Questions on Raoult's Law and Colligative Properties asked in JEE Main

Solution A is prepared by dissolving 1 g of a protein (molar mass = 50000 g mol\(^{-1}\)) in 0.5 L of water at 300 K. Its osmotic pressure is \( x \) bar. Solution B is made by dissolving 2 g of the same protein in 1 L of water at 300 K. Osmotic pressure of solution B is \( y \) bar. Entire solution of A is mixed with entire solution of B at same temperature. The osmotic pressure of resultant solution is \( z \) bar. \( x \), \( y \), and \( z \) respectively are:

Consider the following reactions in which all the reactants and products are present in gaseous state:
\(2xy \rightleftharpoons x_2 + y_2\) \(K_1 = 2.5 \times 10^5\)
\(xy + \frac{1}{2}z_2 \rightleftharpoons xyz\) \(K_2 = 5 \times 10^{-3}\)
The value of \(K_3\) for the equilibrium \(\frac{1}{2}x_2 + \frac{1}{2}y_2 + \frac{1}{2}z_2 \rightleftharpoons xyz\) is:

Given below are two statements:} A semipermeable membrane separates two chambers:

Statement I:} \(H_2O\) molecules move from chamber 1 to chamber 2. Statement II:} The osmotic pressure of a solution prepared by dissolving \(50\,\text{mg}\) of potassium sulphate \((\text{molar mass}=174\,\text{g mol}^{-1})\) in \(2\,\text{L}\) of water (at \(27^\circ\text{C}\)) is \(0.0107\,\text{bar}\). \((R=0.083\,\text{dm}^3\text{bar K}^{-1}\text{mol}^{-1})\) Choose the correct answer.

20 g hemoglobin in a 1 L aqueous solution (A) at 300 K is separated from pure water by semi permeable membrane. At equilibrium the height of solution in a tube dipped in a solution (A) is found to be 80.0 mm higher than the tube dipped in water. The molar mass of hemoglobin is ______ kg mol$^{-1}$. (Nearest integer)
(Given : $g=10 \text{ m s}^{-2}$, $R=8.3 \text{ kPa dm}^3 \text{ K}^{-1}\text{mol}^{-1}$, density of solution $= 1000 \text{ kg m}^{-3}$)}

In sulphur estimation, \(2.0 \times 10^{-3}\) mol of an organic compound (X) (molar mass 76 \(g \cdot mol^{-1}\)) gave 0.4813 g of barium sulphate (molar mass 233 \(g \cdot mol^{-1}\)). The percentage of sulphur in the compound (X) is _______ \(\times 10^{-1}\) % (Nearest integer)

A non-volatile, non-electrolyte solid solute when dissolved in 40 g of a solvent, the vapour pressure of the solvent decreased from 760 mm Hg to 750 mm Hg. If the same solution boils at 320 K, then the number of moles of the solvent present in the solution is ______. (Nearest integer)
[Given: boiling point of the pure solvent = 319.5 K, K_b of the solvent = 0.3 K kg mol⁻¹]

19.5 g of fluoro acetic acid (molar mass = 78 g mol\(^{-1}\)) is dissolved in 500 g of water at 298 K. The depression in the freezing point of water was \(1^\circ C\). What is \(K_a\) of fluoro acetic acid? (For water, \(K_f = 1.86\, K\,kg\,mol^{-1}\)). Assume molarity and molality to have same values.

Two liquids A and B form an ideal solution. At 320 K, the vapour pressure of the solution, containing 3 mol of A and 1 mol of B is 500 mm Hg. At the same temperature, if 1 mol of A is further added... vapour pressure of B in pure state is ___ mm Hg. (Nearest integer)

Elements P and Q form two types of non-volatile, non-ionizable compounds PQ and PQ\(_2\). When 1 g of PQ is dissolved in 50 g of solvent 'A', \(\Delta T_b\) was 1.176 K while when 1 g of PQ\(_2\) is dissolved in 50 g of solvent 'A', \(\Delta T_b\) was 0.689 K. (\(K_b\) of 'A' = 5 K kg mol\(^{-1}\)). The molar masses of elements P and Q (in g mol\(^{-1}\)) respectively, are:

A solution is made by mixing one mole of volatile liquid A with 3 moles of volatile liquid B. The vapor pressure of pure A is 200 mm Hg and that of the solution is 500 mm Hg. The vapor pressure of pure B and the least volatile component of the solution, respectively, are: