Solutions

250g solution of D-glucose in water contains 10.8% of carbon by weight. The molality of the solution is nearest to

(Given : Atomic weights are, H, 1u ; C, 12u ; O, 16u)

 

When a certain amount of solid A is dissolved in 100g of water at 25°C to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is 23.76 mmHg. The number of moles of solute A added is_________.

(Nearest Integer)

 1.80g of solute A was dissolved in 62.5cm³ of ethanol and freezing point of the solution was found to be 155.1 K . The molar mass of solute A is __________g mol^-1.

[Given: Freezing point of ethanol is 156.0 K. Density of ethanol is 0.80 g cm^-3. Freezing point depression constant of ethanol is 2.00 K kg mol^-1]

<p><strong>If O₂ gas is bubbled&nbsp; through water at 303 K, the number of millimoles of O₂ gas that dissolve in 1 litre of water is______________. (Nearest integer)</strong></p> <p><strong>(Given: Henry’s Law constant for O₂ at 303 K is 46.82 k bar and partial pressure of O₂ = 0.920 bar)</strong></p> <p><strong>(Assume solubility of O₂ in water in too small, nearly negligible)</strong></p>

150g of acetic acid was contaminated with 10.2g ascorbic acid $\left(C_6{H}_8{O}_6\right)$ <!-- [if gte mso 9]><xml> </xml><![endif]--> to lower down its freezing point by (x × 10^-1)°C. The value of x is _________. (Nearest integer)

(Given K_f = 3.9 K kg mol^-1; molar mass of ascorbic acid = 176 g mol^-1]

The osmotic pressure of blood is 7.47 bar at 300K. To inject glucose to a patient intravenously, it has to isotonic with blood. The concentration of glucose solution in gL^-1 is __________.

(Molar mass of glucose = 180 g mol^-1 R = 0.083 L bar K^-1 mol^-1) Nearest integer)

The equation

k = <!-- [if gte mso 9]><xml> </xml><![endif]-->  $\left(6.5\times 10^{12}{s}^{-1}\right)e^{-26000K/T}$

Is followed for the decomposition of compound A. The activation energy for the reaction is________ kJ mol^-1 [nearest integer]        (Given : R = 8.314 JK^-1 mol^-1)

2.0g of H₂ gas is adsorbed on 2.5g platinum powder at 300K and 1 bar pressure. The volume of the gas adsorbed per gram of the adsorbent is ______________mL.

(Given : R = 0.083 L bar K^-1 mol^-1)

The osmotic pressure exerted by a solution prepared by dissolving 2.0g of protein of molar mass 60 kg mol^-1 in 200 mL of water at 27°C is_______Pa. (nearest integer)

(Use R = 0.083 L bar mol^-1 K^-1)

1.2 mL of acetic acid is dissolved in water to make 2.0L of solution. The depression in freezing point observed for this strength of acid is 0.0198°C. The percentage of dissociation of the acid is_____________. (Nearest Integer).

[Given Density of acetic acid is 1.02g mL^-1

Molar mass of acetic acid is 60g mol^-1]