What is the maximum boiling point of aqueous solution?

A) Glucose

B) Sodium chloride

C) Calcium chloride

D) Ferric chloride

Correct Answer: D) Ferric chloride

Explanation: Ferric chloride is the compound in which 0.1M aqueous solution has the highest boiling point.

Answer:

(b) As we know greater the value of van't Hoff factor higher will be the elevation in boiling point and hence higher will be the boiling point of solution.

Solution van't Hoff factor (i)

I.0M Na2SO4 I.0M NH4NO3 1.0M KNO3 3 2 2

Hence, 1.0 M Na2St4 has highest value of boiling point.

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Answer:

                (a) As we know from elevation in boiling point that

Unit of

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Answer:

(c) As we know depression in freezing point is directly related to van't Hoff factor (/) according to which greater the value of i greater will be the depression in freezing point.

Solution i

0.01 M glucose 0.01 MMgCI2 1 3

Hence, depression in freezing point of glucose is about 3 times of glucose.

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Answer:

(d) When an unripe mango is placed in a concentrated salt solution to prepare pickle then mango loose water due to osmosis and get shrivel.

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Answer:

(a) According to definition of osmotic pressure we know that n = CRT. For concentrated solution C has higher value than dilute solution. Hence, as concentration of solution increases osmotic pressure will also increase.

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Answer:

(a) According to definition of depression in freezing point
where, Kf = freezing point depression constant, value of depends upon nature of solvent. Kf This is why although the solution have same molality two different solutions of sucrose of same molality prepared in different solvents will have different depression in freezing point.

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Answer:

(b) Number of total ions present in the solution is known as van't Hoff factors (/).

Substances Van?t Hoff factor (i)

For KCl 2

For NaCl 2

For K2SO4 3

Hence, correct choice is (b).

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Answer:

(b) In reverse osmosis, solvent molecules move through a semipermeable membrane from a region of higher concentration of solute to lower concentration.

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Answer:

(a) Value of Henry's constant (KH) increases with increase in temperature representing the decrease in solubility.

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Answer:

                (b) According to Henry's law

As value of K^ rises solubility of gases decreases.

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Answer:

(b) We know that, if a pressure higher than the osmotic pressure is applied on the solution, the solvent will flow from the solution into the pure solvent through the semi-permeable membrane. This process is called reverse osmosis. Thus, in this case, water will move from side (B) to side (A) if a pressure greater than osmotic pressure is applied on piston (B).

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Answer:

(b) van't Hoff factor is the measurement of total number of ions present in the solution. Therefore, greater the concentration of solution greater will be its van't Hoff factor.

	Concentration NaCI
A	0.1 M	On moving top to bottom
B	0.01 M	+ Concentration decreases
C	0.001 M	+ Van't Hoff factory decreases

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Answer:

(b) For an ideal solution, the A?A or B?B type intermolecular interaction is nearby equal to A?fi type interaction. Here, a mixture of bromoethane and chloroethane is an example of ideal solution. On the other hand chloroform and acetone mixture is an example of non-ideal solution having negative deviation. So, (A?A) or (B?B) interaction must be stronger than A?B interaction. While ethanol-acetone mixture shows positive deviation due to weaker A?B interaction in comparison to A?A or/A?B interaction.

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Answer:

(a) When salt is added to water to make the solution the vapour pressure of solution get decreases. This is due to decrease in surface covered by solvent molecule which lead to decrease in number of solvent molecule escaping from the surface corresponding to pure solvent. Hence, vapour pressure also get reduces.

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(a) If two liquids A and B form minimum boiling azeotrope at some specific composition then A?B interactions are weaker than those of A?A and B?B. It is due to the fact that in case of positive deviation, we get minimum boiling azeotropes whereas in case of negative deviation we get maximum boiling azeotropes.

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Answer:

                (d) Given M1=0.02M, V1=4L, M2=, V2=4L + 1L =5L                 As we know,

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Answer:

(a) At specific composition methanol ? acetone mixture will from minimum boiling azeotrope and will show positive deviation. This is due to weaker A ? B interaction than A ? A or B ? B interaction i.e., A ? B < A ? A and B ? B

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Answer:

                (c) Value of
depends upon nature of gases dissolved in water.

Gas Temperature (K) KH/k bar

     Ar 298K 40.3

    CO2 298 K 1.67

    CH4 298 K 0.413

    HCHO 298 K 1.83x10-5

                          Hence correct order is Ar < CO2 < CH4 < HCHO and correct choice is (c).

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Answer:

(a, b) Solubility of gaseous solute in the fixed volume of liquid solvent always depends upon nature of solute but it depends upon pressure at constant temperature and depends upon temperature at constant pressure. Hence, (a) and (b) both are correct.

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(c, d) The solution which follows Raoult's law is known as ideal solution. For an ideal solution intermolecular forces between two benzene molecules are nearly of same strength as those between two toluene molecules. For an ideal solution
Thus, the mixture of benzene and toluene is an example of ideal solution. Option (c) is incorrect as minimum boiling azeotropes are formed by non-ideal solution.

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(a, b) Relative lowering of vapour pressure is a colligative property because (i) It does not depend upon nature of solute. (ii) It depends upon number of solute particles. (iii) It depends upon concentration of non-electrolyte solution. Hence, (a) and (b) are correct.

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Answer:

(a, c) van't Hoff factor (/) is a measure of extent of association or dissociation of solute particles which can be calculated as

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Answer:

(c, d) Isotonic solutions have same osmotic pressure and same concentration. Elevation in boiling point and depression in freezing point are the colligative properties. These two colligative properties depend upon concentration. As the molar concentration is same for isotonic solutions, so elevation in boiling point and depression in freezing point of isotonic solutions must be same.

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Answer:

(b, c) Mixtures having same composition in liquid and vapour phase are known as azeotropes. , Azeotropes boils at same temperature. Here, water-nitric acid and water-ethanol mixtures are non-ideal solution. Hence, water-nitric acid and water-ethanol are examples of azeotropes. While benzene-toluene and n-hexane?n-heptane are examples of ideal solution.

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Answer:

(b, c) The two solutions having same osmotic pressure are known as isotonic solutions. The solute and solvent particles may or may not be same but osmotic pressure must be same.

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Answer:

(a ,d) Depending on the vapour pressures of the pure components 1 and 2, total vapour pressure over the solution decreases or increases with the increase of the mole fraction of component

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