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Which one of the following is incorrect for an ideal solution?

Which of the following statements about the composition of the vapour over an ideal $1:1$ molar mixture of benzene and toluene is correct? Assume that the temperature is constant at $25^\circ\text{C}$. (Given, vapour pressure data at $25^\circ\text{C}$, benzene = $12.8 \text{ kPa}$, toluene = $3.85 \text{ kPa}$)

Of the following $0.10 \text{ m}$ aqueous solutions, which one will exhibit the largest freezing point depression?

The depression in freezing point of 0.01 M aqueous solutions of urea, sodium chloride and sodium sulphate is in the ratio of:

A solution of acetone in ethanol:

An aqueous solution is $1.00$ molal in $\text{KI}$. Which change will cause the vapour pressure of the solution to increase?

The freezing point depression constant ($K_f$) of benzene is $5.12 \text{ K kg mol}^{-1}$. The freezing point depression for the solution of molality $0.078 \text{ m}$ containing a non-electrolyte solute in benzene is:

One mole of sugar is dissolved in three moles of water at 298 K. The relative lowering of vapour pressure is:

A solution containing $10 \text{ g/dm}^3$ of urea (molecular mass $= 60 \text{ g mol}^{-1}$) is isotonic with a $5 \%$ solution of a non-volatile solute. The molecular mass of this non-volatile solute is:

The Henry's law constant for the solubility of $N_2$ gas in water at $298 \text{ K}$ is $1.0 \times 10^5 \text{ atm}$. The mole fraction of $N_2$ in air is $0.8$. The number of moles of $N_2$ formed from air dissolved in $10 \text{ moles}$ of water at $298 \text{ K}$ and $5 \text{ atm}$ pressure is:

The correct option for the value of vapour pressure of a solution at 45 °C with benzene to octane in a molar ratio 3:2 is: [At 45 °C vapour pressure of benzene is 280 mm Hg and that of octane is 420 mm Hg. Assume Ideal gas]

$K_H$ values for some gases at the same temperature 'T' are given: Gas : $K_H$/k bar Ar : 40.3 $CO_2$ : 1.67 HCHO : $1.83 \times 10^{-5}$ $CH_4$ : 0.413 $K_H$ is Henry's Law constant in water. The order of their solubility in water is :

The Henry's law constant $K_H$ values of three gases (A, B, C) in water are 145, $2 \times 10^{-5}$, and 35 kbar, respectively. Determine the order of solubility of these gases in water from highest to lowest:

The plot of osmotic pressure ($\pi$) vs concentration ($\text{mol L}^{-1}$) for a solution gives a straight line with slope $25.73 \text{ L bar mol}^{-1}$. The temperature at which osmotic pressure measurement is done is: (Use $R=0.083 \text{ L bar mol}^{-1} \text{ K}^{-1}$)

Acidified $K_2Cr_2O_7$ solution turns green when $Na_2SO_3$ is added to it. This is due to the formation of:

An aqueous solution of $6.3 \text{ g}$ oxalic acid dihydrate is made up to $250 \text{ mL}$. The volume of $0.1 \text{ N NaOH}$ required to completely neutralize $10 \text{ mL}$ of this solution is

Camphor is often used in molecular mass determination because:

200 mL of an aqueous solution contains 1.26 g of protein. The osmotic pressure of this solution at 300 K is found to be 2.57 × 10⁻³ bar. The molar mass of protein will be: (Use: R = 0.083 L bar mol⁻¹ K⁻¹)

When neutral or faintly alkaline $KMnO_4$ is treated with potassium iodide, iodide ion is converted into 'X'. 'X' is:

The correct order of C-O bond length among CO, $CO_3^{2-}$, and $CO_2$ is: