Solutions practice · Medium

A solution containing $8.6 \mathrm{~g}$ urea in one litre was found to be isotonic with a $5 \%$ (mass/volume) solution of an organic non-volatile solute. The molar mass of solute is;

What weight of hydrated oxalic acid should be added for complete neutralisation of $100 \,{ml}$ of $0.2 {~N}-{NaOH}$ solution?

On dissolving $0.5 {~g}$ of a non-volatile non-ionic solute to $39 {~g}$ of benzene, its vapour pressure decreases from $650 {~mm} {Hg}$ to $640 {~mm} {Hg}$. The depression of freezing point of benzene (in K) upon addition of the solute is..... K.
(Given data : Molar mass and the molal freezing point depression constant of benzene are $78 {~g} {~mol}^{-1}$ and $5.12 {~K} {~kg} {~mol}^{-1}$, respectively)

Which of the following mixture of solutions follow the condition $\Delta_{\text {mix }} H<0$ and $\Delta_{\text {mix }} V<0$ ?

(i) Nitric acid + Water

(ii) Acetic acid + Pyridine

(iii) Ethanol + Water

(iv) Carbon tetra chloride + Chloroform

$K_{s p}$ (solubility product) of $\mathrm{MgS}=\left(\mathrm{Mg}^{2+}\left(\mathrm{S}^{2-}\right)\right)$ is $1.0 \times 10^{-6}$. Thus, elevation in boiling point of saturated solution is $\left(K_b=0.52^{\circ} \mathrm{mol}^{-1} \mathrm{~kg}\right)$

Among the following, the azeotropic mixture is

Assertion : Camphor is used as solvent in the determination of molecular masses of naphthalene, anthracene etc.

Reason : Camphor has high molal elevation constant.

Consider the following statements about osmotic pressure method of molar mass determination.

I. Molarity of the solution is used instead of molality.

II. Magnitude of osmotic pressure is very large even for dilute solutions.

III. Molar mass of biomolecules can be determined as they are not stable at higher temperatures.

IV. Determine the molar mass of polymer as they have poor solubility.

Which of the above statements are responsible for advantage of osmotic pressure for determination of molar mass over the other colligative properties?

Assertion (A) : Addition of solvent to a solution always lowers the V.P.

Reason (R) : The increase in relative surface area give rise to an increase in V.P. for a given solution.

The vapour pressure of acetone at $20^\circ C$ is 185 torr. When 1.2 g of a non – volatile substance was dissolved in 100 g of acetone at $20^\circ C,$ its vapour pressure was 183 torr. The molar mass $(\mathrm{g}\,\,\mathrm{mo}{\mathrm{l}^{ - 1}})$ of the substance is

Assertion: The molarity and normality of a solution of sodium carbonate are same.
Reason: Molarity is the product of normality &amp; valency factor.

How much water is needed to dilute $10 {~ml}$ of $10 {~N}$ hydrochloric acid to make it exactly decinormal $(0.1 {~N})$

Vapour pressure of pure water at $298 \mathrm{~K}$ is $23.8 \mathrm{~mm}$. Thus, vapour pressure of $20 \%$ glucose (weight/volume) solution is $\left(d=0.9971 \mathrm{~g} \mathrm{~mL}^{-1}\right)$

The freezing point of a solution containing $0.2 \mathrm{~g}$ of acetic acid in $20.0 \mathrm{~g}$ benzene is lowered by $0.45^{\circ} \mathrm{C}$. The degree of association of acetic acid in benzene is (Assume acetic acid dimerises in benzene and $\mathrm{K}_{\mathrm{f}}$ for benzene $=5.12 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$)
$\mathrm{M}_{\text {observed}}$ of acetic acid $=113.78$

The amount of ${K}_2 {Cr}_2 {O}_7$ (eq. wt. 49.04) required to prepare 100 ${ml}\,$ of its $0.05 {~N}$ solution is

The amino acid alanine has two isomers, such as
$\alpha-\text{alanine}$ and $\beta-\text{alanine}.$ When equal masses of
these two compounds are dissolved in equal mass
of a solvent, the solution of $\alpha-\text{alanine}$ freezes at
relatively lower temperature. Which forms of
$\alpha-\text{alanine}$ or $\beta-\text{alanine}$, has the larger equilibrium
constant for ionization?

S-I: The boiling point of $0.1 \, \mathrm{M}$ urea solution is less than that of $0.1 \, \mathrm{M} \, {KCl}$ solution.

S-II: Elevation of boiling point is directly proportional to the number of moles of non-volatile solute particles present in the solution.

The molarity of $24.5 \%$ (w/w) $\mathrm{H}_2 \mathrm{SO}_4$ solution having density $1.2 \mathrm{~g} / \mathrm{ml}$ is

Which of the following aqueous solution has minimum freezing point?

If the mass percentage $({w} / {w})$ of urea in aqueous solution is $18 \%$ then the molality of the solution is

Percentage ionization of ${K_3}\left[ {Fe{{\left( {CN} \right)}_6}} \right]$ whose decimolar solution shows an osmotic pressure of 3.94 atm at 300 K is

A certain substance ‘A’ tetramerises in water to the extent of 80%. A solution of 2.5 g of A in 100 g of water lowers the freezing point by $0.3^\circ C$. The molar mass of A is

Osmotic pressure present in the fluid inside the blood cell is equivalent to

Mixture of $1 \mathrm{~mol}$ benzene $(p_{\text {benzene}}^{\circ}=42 \mathrm{~mm})$ and $2 \mathrm{~mol}$ toluene $\left(p_{\text {toluene}}^\circ=36 \mathrm{~mm}\right)$ will have

Which of the following is incorrect?

The vapour pressure of water is 12.3 kPa at 300 K.
What is the vapour pressure of 1 molal aqueous
solution of a non- volatile solute at 300 K?

The density $\left( {i\mathrm{n}\;\mathrm{ g}\;\mathrm{m}\;{\mathrm{L}^{ - 1}}} \right)$ of a ${3.60\;M}$ sulphuric acid solution that is $29\;\% \;{H_2}S{O_4}\left( {\mathrm{molar}\;\mathrm{ mass} = 98\;\mathrm{g}\;\mathrm{mo}{\mathrm{l}^{ - 1}}} \right)$ by mass will be

Assertion: $0.1 \mathrm{~M}$ solution of $\mathrm{NaCl}$ have low freezing point than $0.1 \mathrm{~M}$ urea solution.

Reason: Van't Hoff factor (No. of particles) for $\mathrm{NaCl}$ is more than urea.

The vapour pressure of water at $20^\circ C$ is ${17.54\;\mathrm{mm}}$. When 20 g of a non-ionic, substance is dissolved in ${100\;g}$ of water, the vapour pressure is lowered by ${0.30\;\mathrm{mm}}$. What is the molecular mass of the substance?

Assertion (A): When methyl alcohol is added to water, boiling point of water increases.

Reason ( R ): When a volatile solute is added to a volatile solvent, elevation in boiling point is observed.