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Incorrect statement for Tyndall effect is

Identify the mixture that shows positive deviations from Raoult's Law

Match List-I with List-II
List-I List-II
(A)    negatively charged sol           (I)    Fe$$_2$$O$$_3$$ · xH$$_2$$O
(B)    macromolecular colloid        (II)    CdS sol
(C)    positively charged sol           (III)   Starch
(D)    Cheese                                    (IV)   a gel
Choose the correct answer from the options given below

At 300 K, the vapour pressure of a solution containing 1 mole of n-hexane and 3 moles of n-heptane is 550 mm of Hg. At the same temperature, if one more mole of n-heptane is added to this solution, the vapour pressure of the solution increases by 10 mm of Hg. What is the vapour pressure in mmHg of n-heptane in its pure state?

Which of the following statements is incorrect regarding physissorptions?

Lithium forms body centred cubic structure. The length of the side of its unit cell is $$351$$ pm. Atomic radius of the lithium will be:

$$K_f$$ for water is $$1.86\ K\ kg\ mol^{-1}$$. If your automobile radiator holds $$1.0$$ kg of water, how many grams of ethylene glycol ($$C_2H_6O_2$$) must you add to get the freezing point of the solution lowered to $$-2.8^\circ C$$?

Which one of the following substances used in dry cleaning is a better strategy to control environmental pollution?

The depression in freezing point observed for a formic acid solution of concentration $$0.5 \text{ mL L}^{-1}$$ is $$0.0405°C$$. Density of formic acid is $$1.05 \text{ g mL}^{-1}$$. The Van't Hoff factor of the formic acid solution is nearly: (Given for water $$K_f = 1.86 \text{ K kg mol}^{-1}$$)

The osmotic pressure exerted by a solution prepared by dissolving $$2.0$$ g of protein of molar mass $$60$$ kg mol$$^{-1}$$ in $$200$$ mL of water at $$27°$$C is ______ Pa. [integer value] (use $$R = 0.083$$ L bar mol$$^{-1}$$ K$$^{-1}$$)

Using very little soap while washing clothes, does not serve the purpose of cleaning of clothes, because

The density of 3M solution of NaCl is 1.0 g mL$$^{-1}$$. Molality of the solution is _____ $$\times 10^{-2}$$ m (Nearest integer).
Given: Molar mass of Na is 23 and Cl is 35.5 g mol$$^{-1}$$ respectively.

$$250 \text{ g}$$ 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 $$H = 1u; C = 12u; O = 16u$$)

Boiling point of a $$2\%$$ aqueous solution of a nonvolatile solute A is equal to the boiling point of $$8\%$$ aqueous solution of a non-volatile solute B. The relation between molecular weights of A and B is

The freezing point of a 4% aqueous solution of X is equal to the freezing point of a 12% aqueous solution of Y. If the molecular weight of X is A, then the molecular weight of Y will be

Which of the following statements about colloids is false?

Percentage of free space in cubic close packed structure and in body centred packed structure are respectively

Two volatile liquids $$A$$ and $$B$$ are mixed to form an ideal solution.

$$100\text{ g}$$ of liquid $$A$$ (Molar mass = $$100\text{ g mol}^{-1}$$) is mixed with $$100\text{ g}$$ of liquid $$B$$ (Molar mass = $$50\text{ g mol}^{-1}$$).

If the vapor pressures of pure liquid $$A$$ and pure liquid $$B$$ are $$300\text{ torr}$$ and $$600\text{ torr}$$ respectively, what is the mole fraction of component $$A$$ in the vapor phase?

Which of the following statements about colloids is false?

The correct order of the solubility of alkaline-earth metal sulphates in water is:

The quantity which changes with temperature is :

Given below are two statements:

Statement I: The Henry's law constant $$K_{H}$$ is constant with respect to variations in solution's concentration over the range for which the solution is ideally dilute.

Statement II: $$K_{H}$$ does not differ for the same solute in different solvents.

In the light of the above statements, choose the correct answer from the options given below

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : An aqueous solution of KOH when for volumetric analysis, its concentration should be checked before the use.
Reason (R) : On aging, KOH solution absorbs atmospheric $$CO_2$$.
In the light of the above statements, choose the correct answer from the options given below.

The vapor pressure of pure liquid water at $$298\text{ K}$$ is $$24.0\text{ mmHg}$$. A non-volatile, non-electrolyte solid solute is dissolved in water to prepare an aqueous solution where the mole fraction of the solute is exactly $$0.05$$. Calculate the lowering of vapor pressure $$(\Delta P)$$ of this solution (in $$\text{mmHg})$$. Express your answer to the nearest single decimal place or select the absolute integer value if specified (Report the exact value multiplied by 10 to yield a whole integer: $$10 \times \Delta P)$$.

20% of acetic acid is dissociated when its 5 g is added to 500 mL of water. The depression in freezing point of such water is ______ $$\times 10^{-3}°C$$. Atomic mass of C, H and O are 12, 1 and 16 a.m.u. respectively.
[Given : Molal depression constant and density of water are $$1.86 \text{ K kg mol}^{-1}$$ and $$1 \text{ g cm}^{-3}$$ respectively.

Mass of Urea NH$$_2$$CONH$$_2$$ required to be dissolved in 1000 g of water in order to reduce the vapour pressure of water by 25% is ______ g. (Nearest integer)
Given: Molar mass of N, C, O and H are 14, 12, 16 and 1 g mol$$^{-1}$$ respectively.

Under ambient conditions, which among the following surfactants will form micelles in aqueous solution at lowest molar concentration?

Gold numbers of some colloids are Gelatin: 0.005 - 0.01, Gum Arabic: 0.15 - 0.25, Oleate: 0.04 - 1.0, Starch: 15 - 25. Which among the following is a better protective colloid?

The Tyndall effect is observed only when the following conditions are satisfied,
i. The diameter of the dispersed particles is much smaller than the wavelength of the light used.
ii. The diameter of the dispersed particle is not much smaller than the wavelength of the light used.
iii. The refractive indices of the dispersed phase and dispersion medium are almost similar in magnitude.
iv. The refractive indices of the dispersed phase and dispersion medium differ greatly in magnitude.

Adsorption of a gas follows Freundlich adsorption isotherm. If $$x$$ is the mass of the gas adsorbed on mass $$m$$ of the adsorbent, the correct plot of $$\frac{x}{m}$$ versus $$p$$ is: